Poor layer of the second down ink on the first down ink in multicolor offset printing.

INK

● The tack value of the second down ink is higher than that of the first down ink.(Imbalance of tack)

● Set tack sequence according to the color sequence(subsequent inks must have lower tacks.)

PAPER

● Poor ink absorbency of paper decreases momentary increase of tack, which prevents the first down ink from holding the second down ink properly.

PRESS

● Imbalance of distribution of dampening water among the units breaks the balance of tacks.

● Less amount of the second down ink than the first down ink.

● Improper setting of impression pressure.

● Poor ink transfer due to old blanket.

● Balance the amount of dampening water among the printing units.

●Increase the distribution of the second down ink.

●Adjust the impression pressure.

●Use a new blanket.