Group

Color Deviations


Color deviations can sometimes occur within a print run. They are usually recognisable only when random copies are viewed side by side.

What could cause this phenomenon?

There are numerous causes:

1.

Evaporation of ink solvent

Printing inks contain a fairly high proportion of solvents. Some solvent evaporates during the print run, increasing the pigment concentration - i.e. higher density, accompanied by a darker or more saturated color.

2.

Printing speed

Variations of the printing speed can occur color deviations too.

3.

Squeegee

One other reason for colour deviations can be the squeegee:
Differing in blade hardness, changing the squeegee angle or a defective or inadequate blade edge can cause deviations in color.


Solving the problem

Adding ink as steadily as possible helps to prevent variations in density and viscosity of the ink

Printing parameters established at the art of printing must be maintained throughout the run

The finished result must be continually compared with the original, both visually and by measurment with densitometer

PS Color deviation_EN

Color deviations