General information about the drying process
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General information about the drying process
Drying process
Both inks and coatings are used for offset printing.
Inks and coatings both dry in a different way. Offset
ink dries, to a greater extent, through the chemical
process of oxidation, and to a lesser extent, through
the absorption of mineral oils by the print material.
The coatings used are dispersion coatings, which dry
through the physical process of the evaporation of
the water content.
The drying process must be adapted accordingly.
IR radiation is used to dry printing inks. The use of
IR radiation has advantages in terms of production
and is an efficient technique. This process allows IR
offset inks and conventional offset inks to be dried.
The process of hot air drying in conjunction with
IR radiation and circulating air is used for drying
coatings.
IR radiators
An IR dryer slide-in unit contains a maximum of five
IR radiators. Its output can be manually or automat-
ically set. The IR radiators are cooled by blow air.
The air for cooling the radiators is still applied after
the IR radiators have been switched off to dissipate
the remaining heat generated by the IR radiators
(run-out time). The output of the IR radiators is
reduced to a harmless level to prevent the system
from overheating if the cooling air system fails
during operation.
Other sheet sizes can also be selected for the IR
dryer slide-in unit, thus saving energy.
