Mottle

Ink viscosity is too low

Increase ink viscosity

Ink viscosity is too high

Reduce ink viscosity

Paper stock is too dry

Introduce moist air

Ink is not wetting stock properly

Change blade angle, then change solvent selection

Ink or substrate is too cold

Vary temperature of ink and substrate. Allow to warm to room temperature

Pigment selection is poor

Reformulate ink

Cylinder is too deep

Re-etch or replace cylinder

Print impression is excessive

Reset for lighter impression

Press returned ink is unusable

Increase resin solids. Use fresh ink

Press speed is too low

Increase press speed

Ink might be printing characteristics of substrate

Check alternate substrate for smoother surface

Make sure solvent blend is correct for resin balance

Check solvents (blends) for accuracy – run GC