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CARTON PRINTING
If the cycle rate of the production line is very fast and the ambient temperature is relatively low, the printing dies
could be positioned rotationally downstream of the transfer roll so they print much closer to the leading edge of
the carton. When the coder completes one printing cycle, a portion of the die or all of the die may have already
passed the transfer roll and picked up ink in preparation for printing the next carton. The machine can remain idle
like this for only a second or so before the next carton must contact the print drum or the ink will dry on the die
face and not be transferred to the carton.
Although installing the printing dies in this position restricts how close to the leading edge of the carton you can
register the print, it is one of the only ways to ensure a good imprint on every carton. Since the fastest drying non-
porous inks will dry in approximately 2 seconds at 75 Degree F. ambient temperature, the ink will also dry on the
die face within 2 seconds after it is applied by the transfer roll. If the dies have not contacted the carton surface
before then, no imprint will be transferred to the carton.
If your production cycle rate is not fast enough but you still need to print close to the leading edge of the carton, the
only alternative is to use a slower drying non-porous ink. When making the ink selection, be sure to consider
ambient temperature, it can have a dramatic affect on ink drying times. Hot temperatures make inks dry faster,
cold temperatures retard drying.
