不含 BPA 的热敏纸, which includes a base paper layer, is characterized in that a pre coating layer and a coloring layer are coated on the base paper layer. The oxidant in the coloring layer is 4,4 ‘- dihydroxydiphenyl sulfone, and the sensitizer in the coloring layer is 1,1’ – diphenyl sulfone. The use of this type of thermal paper does not contain harmful bisphenol A oxidants to the human body, and it also produces colors that are suitable for commonly used fax or cash register printers. The function of its pre coating is to cover the original paper surface and improve the surface feel of the paper, while providing a certain insulation effect. During the later stage of printing, the energy provided by the print head is kept in the color layer as much as possible, improving the effectiveness of the color layer.