Thermal paper is a special paper coated

Thermal paper (also known as thermal rolls) is a special paper coated with a chemical formulated to change colour when exposed to heat. Usually thermal paper has two sides, one side like normal paper in general, while one side of the surface is glossier. The glossy surface of the paper will change colour and create writing when exposed to heat from a thermal printer
Thermal paper comes from “base paper” made from wood pulp that is coated with a chemical known as a pre-coating.
This pre-coating fills in pores or spaces between the paper fibers to ensure that the printing surface is smooth and even.

This chemical mixture that is applied as a top layer on the paper is called a thermal layer, which changes color when exposed to heat.

The chemicals contained in the thermal layer are leuco dye, sensitizer, and developer. Leuco dye contains clear crystals that will turn black when the paper is exposed to heat from the printer head

Another chemical substance contained in thermal coatings is Bisphenol-A (BPA) or Bisphenol-B (BPS) which acts as a developer. There is more. Do not forget to also add a sensitizer or light-sensitive liquid to adjust the image activation temperature of the layer.

After adding layers and becoming thermal paper, the paper is rolled into a large roll called jumbo. This Jumbo paper roll is then transferred to a machine that cuts it to various sizes as needed.
Thermal paper is sensitive to heat, this makes it susceptible to light, heat, and other storage and environmental factors that can damage paper if it is stored in poor conditions for a long time.

There are several things to consider when choosing thermal paper

thermal rolls

Temperature and humidity
Do not store thermal paper in an environment with temperature exceeding 140 degrees and high humidity, as this will cause damage to the thermal paper. humidity will affect how it prints on the paper

Thermal paper sizes are in units of miles (one mile is equal to 1/1000 inch). The thicker the mil of thermal paper, the more durable it will be, but that also means less / shorter paper in each roll
How Long Does Thermal Paper Last?