How to balance Taggant
(Marker Ink) with Ink
- Simple Laboratory Test-
- III -
(Written by : N. R. Jayaraman )
PARTICLE SIZE OF THE TAGGANT
The particle size of the pigment or the taggant is very important factor in determining the effective working and balancing of Ink- Taggant. The particle size is always expressed in terms of microns.
Like the pigments in inks, the particle size of Taggants too affect
the print quality unless it blends well with the particles of the colored pigments
present in the ink. So both the pigments and the particle size of the taggant powder plays an
important role wherever they are put to use together.
particle size is measured by simple manual rubbing on particle size measurement
s lab which needs experience to handle or by automatic equipments such as dynamic light scattering (DLS) devices.
Most of the ink pigments fall into the range of 50-200 nm (microns).
Manual Particle size rub Test slab with scale
When the particle sizes of the pigments are in the following range one can
expect trouble free printing and free flow of ink on rollers and ink duct.
Wet offset inks < 5-6 microns
Dry offset inks < 5-6 microns
inks around 20-25 microns
inks <5-8 micron (slightly courser is acceptable –e.g. 15 micron can be run
with a high release anilox but not totally problem free)
or liquid inks which is powder based. Since they are Solubilised dye–the particle size should be theoretically zero micron.
view of the above, if the particle size of the Taggants are kept below 1- 2
micron, it will get blend well with ink to produce excellent result.
opinion the smaller
the size of the
particle, the better will be
tendency to blend well with
the liquid ink , particles being
lighter in weight. To determine the ideal
could be carried
- Get two or three grades of Taggants
particle sizes say mean 5 micron, mean 3-4
micron and mean 2-3 micron and test the
result in the
same way to see
which works better.
- Once you short list the grade then the set of samples can be taken
up for actual machine trial as there will be 10- 15 % variation in performance between machine and lab trials which are manually operated . Such minor variations can be easily adjusted on machines.
The machine trials
could be taken
at the beginning
of the day
when the rollers would have remained
fresh or after the production is completed.
But before taking
machine trials the
inking roller and
ink duct must
be well cleaned
to observe sedimentation or
clogging of the
Since no machine make ready
will be required
and the ink
will have to be simply poured
from the container no special care may
Maximum of three
samples of liquid ink
in three different colors – Violet, Red and Black could be
used avoid mix
up of the samples.
exercise will help in assessing:
- Whether ink
agitator will be
required to ensure perfect blending of Taggant with the ink or not.
- Whether the
final consignment could
be obtained in
small size bottles
of 100 or
200 ml which
can be shaken
well and poured
manually in the
ink duct or directly on
- Whether the Taggant has tendency to sediment if
the ink duct
solution is not
constantly stirred .
- Whether the
Taggant blend well with
the liquid ink
and flow freely
from the ink
duct due to
the continuous rotating action
of the ink
roller which continuously rotates
in the duct once the machine starts working.
- The strength of the solution (percentage
of the Taggant) which needs to be
- Whether adding
10- 20 % thinner at
frequent intervals in
the ink duct continue to maintain desired
result or whether
fresh solution is only needed
to be poured in
the ink duct.
- Since there
will be no
vibrating rollers in
the inking unit , while taking machine trials
the three grades
of solution could
be poured in
three parts with a gap of 1 inch minimum and prints taken so that in one run
of the three samples can be tested without wasting much time .