Broadly categorizing, thermal printers are mainly classified into 2 categories- Direct thermal and Thermal transfer. The direct thermal printer or thermal auto chrome uses a chemically treated thermo chromic paper for printing purposes. On application of heat, thermo chromic paper changes colour and permanent ink marks are left on the surface of the paper. While printing, paper slowly rolls on rollers across the internal heating elements. Areas which get heated starts changing colours to form text or images based on the input.

On the other hand, in case of thermal transfer printing machines, ink is generally held on a thin ribbon. The used ink is wax-like in texture and consistency and when heated, it melts and slowly gets transferred onto the printing paper. Heating elements are quite similar in shape, design and features for both these types of printers.

Next, coming to the common applications of the thermal transfer printer, generally they are used for printing labels like barcodes, clothing tags etc. Thermal transfer printing machines are highly preferred mostly because off their high speed, accuracy and high levels of perfection. Moreover, durability of the images printed using such printers are remarkably higher which adds to its tally of offerings. Furthermore, label printers come handy for printing labels for multiple purposes using numerous varieties of ink depending on individual preferences and the surface and type of material on which it’s being printed.

Direct thermal printers, on the other hand, enjoy widespread application in the industrial sectors, mainly because of their terrific speed and efficiency. The biggest advantage of using this type of printer is the fact that it does not use any ink at all. The only investment therefore is the printing paper and nothing else. This adds to the convenience of the users. Along with this, these printers have a reasonable durability and can run for years with a minimal maintenance. They find common application in credit card machines, ATM counters and cash registers for their enhanced durability.

Both these types of printers are rising in popularity and demand with time, mainly for their speed and accuracy. They have a very few moving parts that contribute in making them highly reliable and efficient. Images printed are very clear and durable as well.

Earlier, direct thermal printers had a problem in terms of quality of the printed images on being exposed to heat or water. However, with advancement of technology over the years, such problems have successfully been resolved by now. However, comparing between the two, direct thermal models are definitely better compared to the thermal transfer ones simply because it does not consume any toner or ink unlike the later. However, talking of quality, thermal transfer offers greater options and varieties but the fact that it consumes a lot of toner comes as a problem for many, particularly in the commercial sectors where a lot of copies need to be printed on a regular basis. Also, direct thermal printer offers limited colour options which renders it unsuitable for the printing jobs that requires more varieties