Thermal paper, also known as thermal fax paper and thermal recording paper, belongs to a kind of processing paper. There is no doubt that thermal paper has become an indispensable paper material in daily life. In daily life, thermal paper is widely used in supermarket shopping receipts, general movie tickets, taxi tickets, POS signature when swiping credit cards, ATM receipts, fax paper and so on.
Many bank practitioners and users who don't know the truth are worried that thermal paper is poisonous and will cause harm to their health. Is that the truth? Before answering the question, it is necessary to understand the construction principle of thermal paper.
Thermal paper is a kind of processing paper, its manufacturing principle is to coat a layer of "thermal paint" (thermochromic layer) on high-quality base paper. Although there are more than a dozen chemicals used in this chromophore, there are at least the following compounds:
Colorless dyes, which are widely used, are fluorescent compounds.
The chromogenic reagent accounts for less than 20%, and the commonly used ones are bisphenol and p-hydroxybenzoic acid.
Sensitizers accounted for less than 10%, which contained benzenesulfonamide compounds.
The filler accounts for less than 50%, and calcium carbonate (particulate matter) is commonly used.
Adhesives account for less than 10%, such as polyvinyl acetate.
Stabilizers, such as diphenyl p-phthalate;
Lubricants, etc.
Therefore, the small thermal paper production process is difficult, and the technical requirements are high.
Thermal paper prints text images mainly by thermal coating. Nowadays, many regular thermal papers mainly focus on three defenses, which can isolate thermochromic compounds very well. These thermal papers do no harm to people.
But now there is no standard thermal paper in our country. Some thermal papers manufacturers coat many of these chemicals, which makes thermal papers unhealthy. Some manufacturers use general thermal papers to impersonate three-proof thermal papers.
Thermal paper is rich in bisphenol A. "Bisphenol A" has certain toxicity. People with open wounds are best not to touch paper such as thermal paper. Low-grade thermal papers containing bisphenol A are still ubiquitous in our lives. But don't be too frightened.
Experts have shown that bisphenol A is attributed to low toxic chemicals. It is very stable at room temperature. Only when it reaches a certain dose can it bring health risks to the body.
But just in case, we have to take corresponding measures.
How to reduce the damage of bisphenol A?
1. Don't let children touch the receipt in case they put it in the entrance.
2. Keep the printed receipt in an envelope separately to prevent other things from infecting BPA.
3. When using ATM to withdraw money or refueling at self-service gas stations, do not print receipts as much as possible, and try to reduce the time to touch such receipts.
4. Finally, wait for the ticket to be printed out thoroughly and the temperature to drop before touching it. When sweating or hand trauma, try to avoid touching thermal paper, especially don't hold the thermal paper receipt tightly in your hand, avoid opening the pore when sweating, and increase the possibility of BPA entering the human body through the pore.
5. The printed receipt is not very useful. It is advocated that the receipt be discarded as soon as possible. Because the acetone and phenol in bisphenol A are volatile substances, if they are kept in the place where the human body can touch for a long time, they will cause damage to the human body.
6. After touching the receipt, wash your hands before eating. Because acetone and others are water-soluble, they can be taken away in the process of hand washing. But don't wash your hands with alcoholic liquids, because alcohol can add to the absorption of BPA by your skin.