Tech Tip Tuesday: Incorrect Pad Printing Ink Amounts
Too little pad printing ink, often times the ink will not “flow” in the inkcup correctly giving an inconsistent fill of the etch. Additionally, the ink will tend to thicken much more quickly as the doktoring action of the cup allows for thinner to flash. In cases where hardener is used, very short pot life can be expected of the ink. We do have an “Ink Saver” device that allows for combating the first issue with companies that have short runs where it does not make sense to mix enough ink to fill the cup to the recommended ½ to ¾ full level.
Too much pad printing ink, the process can get messy. In particular when hardener is used. A byproduct of the addition of a catalyst (hardener) is off gassing. If this gas has no place to go, it tends to cause the cup to hydroplane as it pressurizes the inkcup. The ink that is left behind is then “plowed” into pools of ink usually on either end of the travel of the inkcup.