Printing Ink

Printing Ink
The ink used in offset printing is usually a highly viscous
mixture having the basic components of ink pigment,
vehicle (binder), additives, and carrier substance.

Ink pigments can have either an organic or inorganic
nature. The pigments determine the hue of the printing
ink. They consist of solid, irregularly-shaped particles
that are about 0.1–2 μm in size.
Vehicles (binders) are needed to bind the pigment,
which is supplied in powder form, to the substrate.
Vehicles also form a protective film around the
pigments so that they are protected from mechanical
abrasion. The composition of the vehicles depends on
the printing technologies and substrate to be used.
The vehicles used in the production of printing ink
are also called “varnishes”. The real know-how of the
printing ink manufacturer lies in the creation of
the formula and the preparation and combination of
the individual raw materials which make up the
vehicle.
Additives can be mixed into the ink to achieve specific
properties and to overcome specific printing problems.

Mineral oils are used as carrier substances for offset
inks. They fulfil the function of transporting the ink
and are removed again in the drying process (evaporation,
absorption). Conventional offset inks dry by
absorption, evaporation and, depending on the type of
ink, oxidation.

In addition to these most commonly used inks, there are inks that
cure by radiation cross-linking. The structure of these inks is
completely different than that of conventional inks.UV
inks are available for both conventional (with dampening
solution) and waterless offset printing.

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