• North America
    Most Selected Countries
Offset Coating

Offset Coating

Effect pigments in offset coating allow creative designs on various materials. For the best results and intensive and premium effects, certain things must be taken into account. First, selecting the right etched rollers and photopolymer plate plays a very crucial role – both for defect-free printing and for a good effect.

The cell geometry of the etched rollers and the effect pigments used should be matched in accordance with the table below.


Pigment Particle SizeTheoretical Dispensing Volume (cm3/m2)Screen Angle HexagonalLines/cmLines/inch
< 15 μm
5–25 μm
6–1360° or Hachure80–120200–300
10–60 μm9–2060° or Hachure60–100150–250
10–100 μm
10–125 μm
20–2560° or Hachure40–60100–150

Stop Crushed Edges

To stop crushed edges, it is generally recommended to affix base leaders to the polymer plates. For double coating applications, it must also be ensured that the base leaders for the two coating units are next to each other.

Offset coating with half-tones
Innovative types of etched roller transfer the pigments better and allow the use of effect pigments in half-tone applications. The ratio of the particle size, screen ruling, and theoretical dispensing volume is decisive for selecting the right etched roller.

Autotypical half-tone screens (ART) with a screen ruling of 21 lines per centimeter (52 lines/inch) are the most suitable for presenting half-tones using effect pigments. Grain or frequency modulated screens are not recommended due to the platelet structure of the effect pigments.

Pearlets Pigment sizePrint140 Lines/cm
12,5 g ART
100 Lines/cm
8,5 g ART
100 Lines/cm
16,0 g ART
80 Lines/cm
20,0 g ART
5–25 μmFulltone++++
10–60 μmFulltone++++
20–100 μmFulltone-+++
20–125 μmscreen----
ART is the registered trade mark of Praxair (
+ printable
- unprintable