Davis points out what ink combinations and procedures will and worn't work for special-effects applications.
By Rick Davis
The one exception to this rule is when a design calls for a high-density ink, which must be printed last and necessitates flashing of the metallics before they are overprinted. See the next section to learn more about high-density inks.
Do always print high-density as the last special-effect ink in any printing sequence
This guideline bears consideration for several reasons. First, you would not want to depress a high-density print with subsequent print since it could adversely affect the overall height of the high-density ink film. Additionally, overprinting would mean that the high-density ink needs to be flashed. Finally, after flashing, a high-density ink film provides an inconsistent printing surface, which could adversely affect the continuity of any subsequent ink printed over it.
Do engineer prints so that multicolor puff effects are achieved with a single white-puff underbase
In other words, don't attempt to print excessive numbers of puff-ink colors. Instead, overprint the white-puff underbase with the conventional plastisol colors that the design calls for.
Although you can stagger your mesh counts when printing multiple puff colors, the required flashing will cause you to sacrifice resolution and overall height of the puff effects. I have seen instances where printers have tried to print four, five, or six individual puff colors and ruined the overall appearance of the design because the colors wouldn't flash properly.
Don't attempt to produce fine details when printing with most special-effect inks
Due to the courser mesh counts that most special-effect inks require, producing fine details is typically impossible. If the required detail is too great on a puff print, you will sacrifice the puff height for detail. On inks such as metallics, glitters, or reflectives, excessive detail will restrict passage through the stencil of larger special-effect ink particles, which can result in clogged screens.
Don't print large image areas with high-density or puff inks
The total height of the ink film in both puff and high-density printing applications is determined by a combination of the mesh and stencil thickness. The center of large image areas (open mesh areas) get no support from the stencil. This can result in a slightly concave ink deposit as the deposit thickness will be greater near the edges of the open area than the center. This concave profile will prevent you from achieving the desired high-density or puff effect.
Did you enjoy this article? Click here to subscribe to the magazine.