PRD - pastel red image
PYL - pastel yellow image
Films with a matte surface on the reverse side have the suffix M. For
example, sepia (KSPM), blue (KBLM), or black (KBLM) have a matte surface.
The matte surface accepts either pencil or ink for additions or
corrections to the foil.
Diazo foils do not have a long shelf life. You should keep the unopened
packages refrigerated until ready for use; however, you must allow time
for the foils to reach ambient temperature prior to using them.
e. Exposing and Developing the Diazo Foils. Before you can expose
and develop the film you must start and adjust the machine. Ensure the
ammonia storage tank is filled to capacity, insert the drain tube into
the residue bottle, and if the ammonia feed is not an automatic function
of the machine, turn on the feed switch. Then turn on the machine and
adjust the ammonia system to feed 50 to 60 drops per minute. Allow the
machine a warm-up period until the temperature of the chemicals reaches
180 to 210.
If bubbles appear in the ammonia during operation, the
machine has heated the ammonia too much. You can correct the temperature
of the ammonia by adding 1/8 to 1/2 cup of cold water.
(1) Positioning the master and foil. Remove the diazo foil from
its lightproof package (the foils have a nick in one corner). Then place
the master on top of the emulsion side of the foil, face up, ensuring you
have the nicked edge of the foil in the top left- hand corner when facing
the foil. Having the nick in this position ensures the emulsion side of
the foil is properly positioned against the backside of the master.
Place the foil and master on the slip sheet that came with the foil
Slip sheet, foil, and master ready for exposure
Feed the slip sheet, diazo foil, and master into the printing section of
the machine. The speed at which the trio (slip sheet, foil, and master)
travel varies, depending on the color of the foil. Unfortunately, you
have to use a trial and error