Thermal Paper

Thermal paper is a special type of paper coated with a heat-sensitive chemical layer (typically leuco dyes plus a developer like BPA or BPS). When a thermal printer’s heating element passes over the paper, the coating darkens, producing the printed text or image without ink, toner, or ribbons.

It’s the dominant medium for retail receipts because thermal printers are silent, fast, mechanically simple, and consume nothing but paper. The trade-off: thermal receipts fade over time, especially in heat or sunlight — a 6-month-old receipt left in a hot car can become unreadable.

Standard thermal receipt paper is 80mm wide for retail and 57mm wide for gas pumps and tickets. Both come on rolls of varying lengths. Most grocery and big-box stores in the US use 80mm.

BPA-free thermal paper is increasingly common due to health concerns about handling thermal receipts in volume (cashiers, bartenders).