Impressions - August 2018 - 39

Adding it Up
Once you have a basic line of colored inks, consider additives to round out your arsenal.
A glossy ink can be given a matte look by adding a small amount of dulling additive or paste.
Texture and dimension easily can be achieved with a puff additive.
Similarly, to add adhesion to an ink for nylon garments or duffle bags, add some nylon catalyst.
(Tip: After it's cured, wait 24 hours to see improvement in adhesion.)
It's not necessary to have an ink system that does everything. Expect to need an assortment of
additives and other tools to achieve the looks your customers are demanding.

If your film isn't as opaque as it should
be, then you may lose some design details.
One solution is to reduce exposure time,
but doing so may result in more pinholes
or the emulsion may break down prematurely during a print job.The subtle halftones also may not have the desired look.
I understand that in the real world there
is some forgiveness with film opacity, but
total blackout is the goal.With opaque film,
things are easier, faster, better, and more
productive and forgiving.The amount of
image degradation from the original all
depends on the quality of the processes
that occur before ink is applied to the
substrate.
If you find yourself in a
quandary, before hitting the panic
button, ask your vendors for help.

Not Enough Emulsion
Sometimes, less-experienced printers don't
use enough emulsion on the shirt side
of screens or they improperly dry them.
There must be enough emulsion on the
bottom of the screen so it can properly
prevent the ink from spreading.
Emulsion's job is to hold back the ink
so that it can accurately duplicate the
design on the film. Remember, the film
is a copy of the art and the screen is a copy
of the film. The printed image will not
improve from the original, but emulsion
is an important step for producing a print
that is as close to the original as possible.
To gauge whether you have a sufficient

emulsion layer, feel its edge where the
design is located. If you don't feel a distinct
edge, there isn't enough. Always dry the
coated screens horizontally with the ink
side up. Avoid using fans to shorten the
drying time, as this only allows dirt and
particles to accumulate on the screen,
and may create pinholes, etc.
Adequate amounts of emulsion also
will control the ink-deposit amount,
thus affecting its opacity. To eliminate
the amount of print strokes required to
achieve a more opaque print, add extra
emulsion to the screen's shirt side. This
also may save printing time and increase
your shop's bottom line.
Using One White Ink
Beginning printers generally use just one
color - in many cases, white ink - for
their designs. However, it's ideal to use
several types of white ink during screen
printing: one for cotton, another for lowbleed ink, another for 100% polyester
and more.
Using one white ink for everything
could lead to a troublesome scenario.
White ink intended for cotton can bleed
when printed on a colored substrate that
contains polyester. The low-bleed and
polyester white inks could create a ghost
image when used on dyed cotton garments. A low-bleed white ink may not
be strong enough to block dye migration
when used on 100% red polyester fabric.
Such scenarios continue when more fabric
types are considered.
You may be wondering why there isn't
just one ink line for everything you may
need to print.The reality is that decorators,
and even their customers, want different
types of prints. Some are strictly concerned
with opacity, while others prefer a matte
finish. Some may require more adhesion
for nylon duffle bags, for instance.
What about those who want a perfect
Pantone color match? Others require a
softer feel. The situation is even more
complex when the myriad substrates are
considered - cotton, nonwoven polypropylene, dyed polyester and stretch swimsuit
materials - all requiring different types
of inks.
AUGUST 2018

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Impressions - August 2018

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