Thermal paper is probably most well known as the original fax machine paper. The slick paper is infused with a chemical that reacts to heat by turning black, or sometimes blue or red. Fax machines and other machines that use thermal paper apply heat to it in the shape of letters and other graphics to produce the printed resulting documents. There are other uses for thermal paper as well.
Facsimile (Fax) Machines
The original fax machines, and some current models, use thermal paper to produce the printed fax documents. The paper comes in rolls and is installed inside the machine. When a fax is received, the machine prints the transmission on the paper and dispenses the pages out the front of the machine, cutting it off at the end.
Credit and Debit Card Machines
Thermal paper today is still widely used in credit and debit card machines. Customers swipe their credit or debit cards through a magnetic reader that completes the sale electronically. Once the transaction is finished, a thermal paper receipt is issued containing all pertinent information. The paper comes on narrow rolls that are installed directly in the magnetic reader machine. The machine severs the thermal paper with a cutter after the receipt is issued.
Portable Point-of-Sale (POS) Systems
Portable Point-of-Sale systems employ thermal paper in narrow rolls as well. For example, when a customer returns a rental car, the rental car company agent is able to print out a receipt in the auto return area so that the renter can be on her way instead of having to visit a service desk inside the agency building. Another example of a POS system that uses thermal paper is portable credit and debit card machines used by vendors at an outdoor festival or art fair. These machines use narrow rolls of thermal paper as well.
Automatic Teller Machines (ATMs)
One of the most common uses of thermal paper is in the automatic teller machines at banks. After the client completes his banking using the touch screen or keyboard, the ATM prints out a receipt of the transaction on thermal paper. This thermal paper, too, is of the narrow-roll type.
Thermal paper is used with some models of portable pocket printers such as the Pentax and Brother PocketJet series of printers. These machines require a sheet form of thermal paper instead of rolls.
Thermal paper is also used to generate lottery tickets. The latest technology in thermal paper makes it possible to use it for this purpose. That is, the stability of the paper to not react with skin oils and other contaminants that the earlier versions were prone to do.
Long-Term Storage Documents
Thermal paper is also used today in a new generation of medical documents, bank statements, and other paperwork that needs to stand up to a long-term storage situation.