Looking for the perfect grades of thermal paper can sometimes be difficult. This is caused by numerous manufacturers who each use their own thermal paper grading system. Despite this there are several factors which help to decide the grades of thermal paper in any ranking system and these are Sensitivity, Environmental Resistance, Archivability Years and Caliper.
Sensitivity is one of the more important factors when you are looking at high quality prints on thermal paper. The sensitivity of thermal paper denotes how fine, and sharp image and text appear. Low grade thermal paper can make text appear diffused, and images blurry.
Environmental Resistance is another important factor, especially if the thermal paper will be exposed to varying conditions such as heat, light, and moisture. Even things as minor as the oil on a person's fingers can cause damage to low grade thermal paper. If your thermal paper is going to be exposed to the elements, it is essential that you use a high grade thermal paper with a high environmental resistance.
When you see archivability years grades on thermal paper packaging it is simply referring to the lifespan of text and images on a page before they fade. Due to the chemical nature of thermal paper a certain quality is required to hold an image or text for decades to come, some low grade thermal paper may lose its contents in a short space of time, even when archived and stored in a dry dark box.
The Caliper of the paper is simply the thickness. The thicker paper is often more durable than thinner thermal paper types.
The top grades of thermal paper, whether the thermal grades are measured in numbers, or names, will often have a good level of survivability and quality in all four of the above areas. However you can sometimes save costs by buying thermal paper which specialises for your needs, for example thermal paper which will be archived will not need to have a high environmental resistance.