Instead, they are printed using thermal paper and special heat-based print heads. Tiny heating elements inside the printer heat the chemical coating on specific areas of the paper, creating dark marks.
In other words, the printer does not put ink onto the paper. It uses heat to create the text.
This is also why the printing does not last forever. Heat, light, ultraviolet radiation and moisture can affect the paper’s chemical coating over time, causing the printed text to gradually fade and, in some cases, almost completely disappear.
One major advantage of thermal printing is its speed and simplicity. Compared with conventional ink printers, thermal printers are fast and quiet, while there is also no ink or toner to run out.
That is why thermal printers are widely used for printing quick receipts at ATMs, shops and other locations.
However, if a receipt could become important evidence in the future, it is better not to rely only on the physical paper. Taking a digital photo of the receipt as soon as you receive it is a more reliable way to preserve the information.
So, the next time your receipt looks blank after a few months, remember: the ink did not disappear. There was never any ink on it in the first place.
