First we'll define 'direct thermal' labels versus 'thermal transfer' labels.
When using 'thermal transfer' labels it is necessary to install a roll of inked ribbon into the printer along with the labels. The ink from the roll of ribbon transfers to the labels as they are printed.
Rolls of inked ribbon are not used when printing on 'direct
thermal' labels. The heat generated from the print head elements causes a
chemical reaction to occur on the label surface which creates a black image to
It works similar to receipt paper.
If the roll of labels is not clearly marked as being 'direct thermal' labels then you can follow the steps below to determine if they are direct thermal.
Tear off a label or a few if they are small and place them on a flat surface.
Using your fingernail* and a quick flick of the wrist, scratch the surface of the label.
If the labels are 'direct thermal' then you will see a clear
black streak where the label was scratched.
A scratch that is not black will appear if your labels are not direct thermal.
*A plastic pen cap can be used instead of your fingernail.
Here is a video showing a label scratch test. Read More>>
Contact the distributor that supplied you with the labels if they are not the correct type.