HP 4100TN - Manual (Page 195)

EN Paper specifications 193
Note Do not use letterhead paper that is printed with low-temperature inks,
such as those used in some types of thermography.
Do not use raised letterhead.
The printer uses heat and pressure to fuse toner to the paper. Make
sure that any colored paper or preprinted forms use inks that are
compatible with the printer’s temperature of 230° C (446° F) for
0.05 second.
Avoid using paper that has been damaged due to having already been
used in a printer or copier. (Do not print on both sides of envelopes,
transparencies, or labels.)