The inking and dampening
rollers in the offset machine are very important
components for transporting the ink and to
dampen the printing plate. Due to their various functions in the
machine the rollers are subject to various
demands and require special care and
rollers or rollers with surfaces damaged by
solvents are frequently important sources of
is therefore necessary to check their
Store-hardness. This hardness test according to standard
DIN 53505 (“shore A”) is carried out with a
handy test instrument, whereby a truncated
cone-shaped needle is pressed into the surface
of the roller covering by means of a spring. The maximum depth of penetration is
measured. The readings on the indicator are from 0 to 100 in steps of 5 Shore hardness
on the function of the roller, the required
Shore hardnesses vary.
use of cleaning agents to clean the rollers also
frequently causes printing problems. Fluids, which are injurious to rubber,
must never be removed with unsuitable tools such
as a wire brush or emery cloth.
guidelines for care and maintenance of rubber
products are given in standard DIN 7716.
industry has developed special cleaning and
maintenance materials, which give excellent
results, even in extreme cases and which help to
preserve the roller covering.
from the roller manufacturers concerning the
treatment and storage - before and during use - of
rollers covered with elastic materials should
also be strictly observed.
Only well maintained inking and dampening
rollers guarantee good and consistent printing
quality, long working life and permit rapid ink