One of those rollers can have a series of pockets in its roll face to receive additive formulation from a reservoir and to define {HEAD ~ the pattern} of {TAIL ~ the formulation} on the paper 
One of those rollers can have a series of pockets in its roll face to receive additive formulation from a reservoir and to define { HEAD ~ the pattern } of { TAIL ~ the formulation } on the paper
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH