What is the best type of emulsion to use for screen printing with discharge inks?
A pure diazo emulsion works well for water based and discharge inks. It has longer exposure times, but exhibits excellent water resistance once exposed and dried.
SBQ pure polymer emulsion with added diazo also works. This exposes a bit faster, but I've found that I can hold finer detail with a pure diazo version.
There are also emulsions made specifically for discharge and water based printing.