Inkcups ICN-B100, Руководство пользователя

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INKCUPS PAD PRINTERS ICN-B100
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INK PICK UP AND TRANSFER
As the pad lifts, the tacky surface of the ink sticks to the pad and lifts out about half of the
depth of ink in the etching. This layer of ink is carried towards the print area. During the action,
some of the solvent evaporates from the exposed surface of the ink on the pad and this
surface becomes tacky. When the pad contacts the components. The film of ink sticks to the
surface and separates from the pad as it lifts up. The pad has to be shaped such that when it
compresses, the pad surface describes rolling motion. This motion is important as it
squeezes out the air over the plate and the ink surface.
THIN FILM PROCESS
The ideal situation is when the maximum
amount of ink is picked out of the etching by the
pad and all of the ink film is transferred from the
pad to the object. Pad printing is a thin film
process. Starting with an etch depth of 25
microns (1 micron is 0.001 of a mm) about half
of that ink film is picked up. Of this wet ink film,
60% is solvent which evaporates leaving only 5
microns of dried ink deposit. It is easy to see
how susceptible such a thin film can be to
changing temperatures, humidity levels, static
charges, and variations in airflow. Controlling
the rate of evaporation of the solvents from the
ink and maintaining the correct solvent balance
are the keys to successful pad printing. If the solvents evaporate too quickly the ink might not
even pick up from the plate because it has dried in the etched portion of the plate. If the
solvents evaporate too slowly, the surface of the ink may not be tacky enough to stick to the
pad and lift from the etch. Both conditions, although extremes, will have the same effect --
little or no ink on the pad. Having picked some ink up from the etching onto the pad, if
solvents evaporate too quickly, ink dries and stays on the pad. If they evaporate too slowly,
only some ink will release from the pad onto the substrate. Therefore, it is important to have
the right time for ink pick up and printing.
ITEMS TO START A PAD PRINTING JOB
™ Etched plate
™ Silicone rubber pad
™ Ink and thinner
™
Fixture