How to identify the quality of the cash register paper rolls?

The printing roll paper first looks at the appearance of the paper. The heat sensitive silver paper with good quality has uniform color, good smoothness, high whiteness and a little green. If the paper is very white, the protective coating and the thermal coating of the paper are not reasonable, adding too much phosphor. If the paper finish is not high or it looks unevenly, the paper coating is uneven, and if the paper looks strong, it also adds too much phosphor. Then the heat is heated on the back of the paper with fire. If the color of the paper is brown, the heat sensitive formula is not reasonable and the storage time may be short. If the black part of the paper has small stripes or the color block is uneven, it shows that the coating is not uniform. After heating, the quality of the paper is black green, and the color block is uniform, and the color gradually fade from center to periphery.