Summary
Highlights
Thermal printers operate by applying heat to specific areas of white, chemically treated paper. The heated areas turn black, forming the desired output. Unlike inkjet or laser printers, thermal printers do not use ink or toner, relying instead on the chemical reaction within the paper itself.
Thermal printers are notably quiet, with the only audible sound usually being the motor feeding the paper. Because they use heat, users must be cautious about exposing the printed output to other heat sources, which can cause the entire page to turn black. Some clear tapes can also react with the thermal paper, turning the affected area white.
Due to the absence of ink or toner and the use of specialized paper, thermal printers have a relatively simple construction. Key components include a feed assembly, often a friction-based roller, that moves the thermal paper through the printer, and a non-moving heating element that spans the entire printing area. Heat is applied to the element as the paper passes, creating the print.
Thermal printers require a special type of paper called thermochromic paper, or thermal paper. This paper has a chemical coating that changes color when exposed to heat, making regular paper unsuitable. Thermal paper is commonly used for receipts, shipping labels, and credit card terminal printouts. It has a distinct glossy and textured feel compared to standard printer paper.