Production method: thermal paper such as 57mm thermal paper roll is a kind of processing paper, the production method is simply to coat a layer of "thermal coating" (thermal chronotropic layer) on high-quality base paper.

There are more than a dozen kinds of chemical medicine used in this discoloration layer, including:

(1) Leuco dye, or silver dye, because of its variety, there are different colors in the handwriting, blue, purplish red, black and so on. The commonly used leuco dyes are crystal violet lactone (CVL) with the triphenylalkylphthalein system, fluorane system, colorless be

(2) Chromogenic agents, commonly used are bisphenol A, p-furyl benzoic acid, and its esters; nzoyl methylene blue (BLMB) system or snail mannan system.

(3) Intensifier, commonly used is benzenesulfonic acid amides;

(4) Fillers, the most commonly used is calcium carbonate;

(5) Adhesives, commonly used are polyvinyl alcohol (PVA),  methylcellulose, denaturated starch, CMC, ethylcellulose,  polyvinylpyrrolidone, alkyd resin, polyester resin, polyacrylamide, multicomponent polymer with ethyl acrylamide as the center, PVA graft polymer, etc.

(6) Image stabilizer, commonly used are hindered phenols, acrylic acid symplectic acid, zinc stearate, epoxide, p-phthalic acid dibenzoyl;

(7) Lubricant, usually waxy substances, such as alkane paraffin, stearic acid amide (octadecyl amide).