Thermal coating and protective layer that influence its quality mostly.
Thermal paper rolls are always divided into three layers, the bottom layer is paper base, the second layer is thermal coating and the third layer is protective layer, thermal coating and protective layer that influence its quality mostly.
If the protective coating of thermal paper rolls is uneven, printed pictures will be with bad quality, somewhere is with strong color while somewhere is with light color, if the chemical recipe of thermal coating is unreasonable, it will cause short retention time, good printer paper can be stored for 5 years( in the condition of normal temperature without direct sunlight), nowadays, some thermal paper rolls can be stored for 10 years,if the chemical recipe of thermal coating is unreasonable, it just can be stored for several months.
Protective coating is important for retention time, it can absorb part of light that can make thermal coating produce chemical reaction for retarding printer paper goes bad, it also can protect the thermal element of printer from damaging. However, if the chemical recipe of thermal coating is unreasonable, the protection for thermal coating will be reduced, even in the process of printing, there will be some small grains fall off to rub thermal elements of printer and damage the thermal elements.