I offer this lengthy post for two reasons:
a. To invite the "lurker" to try this wondrous process. It is
neither easy nor impossible.
b. To invite those more knowledgeable and experienced than myself
to critique my ways & means, thereby improving both my work and that of
legions sure to follow.
If you do not already own it, purchase Luis Nadeau's superb book
"Modern Carbon Printing". ISBN 0-9690841-3-7. Do not skip doing this!
The Ingredients
Two parts:
a. the support paper (tissue)
b. the glop (emulsion)
The "Tissue" paper
Rising drawing bristol 1-ply plate (DS cat # RJ8067012, 22" x 30" sheets
are 69 cents each. See DS phone # below.)
Soak this paper at room temp for 10 minutes in distilled water while you
are preparing The Glop.
* A note on water: Tap water varies from one community to another and
from season to season. My life was simplified by the purchase of a
reverse-osmosis water treatment system. This device provides consistent
water which approaches distilled water in quality. Otherwise, visit
your friendly grocer for distilled or R.O.-treated water at perhaps 90
cents per gallon.
The Glop
1000 ml distilled water
10 ml glycerin
10 grams household granulated sugar
100 grams gelatin (Knox unflavored, 7 grams per envelope)
10 ml pigment (black Sumi ink Cat. # RJ4006010 from Daniel Smith in
Seattle WA, USA phone 800-426-6740 $3.54/2 oz.)
The Procedure
a. All ingredients at "room temperature" 68 F. Pour pigment,
glycerin, sugar and water into large-mouth heatable beaker. My favorite
is a "gravy separator" a pitcher-like device which allows the poured
liquid to issue from beneath the surface and thus eliminate bubbles &
foam. Mix.
b. Add gelatin & stir gently so gelatin is wetted. Let sit for 1/2
hour. The gelatin will swell and the mixture will thicken.
c. Heat this mixture to 120 degrees F, but *NO HOTTER* I prefer to
heat the "beaker" in a water bath for easier control & gentleness. We
don't want to cook the gelatin mixture.
Coating the Tissue
1. Place a sheet of the pre-soaked tissue paper on a clean sheet of
glass and squeegee to remove excess moisture.
2. Lay a wooden or metal frame atop the wetted paper and clamp into
place. A small picture frame would work. I make my own metal frames
for this. The frame merely contains The Glop so it doesn't run all
over.
3. Pour the heated emulsion onto the wetted paper to provide a thin,
even coating. I use 30ml for a coated area 6 inches by 7 inches on
which I will print a 4x5 negative.
4. If there are bubbles in the liquid emulsion, a common hair comb
works well to herd them to the edge out of the picture area. Bubbles
are a problem. The above-mentioned "gravy separator" pitcher helps.
5. After 10-20 minutes, the emulsion will have cooled and "set". Run
a pencil tip around the edge of the frame to break the attachment of the
coating from the frame. Remove the frame. Pin the coated tissue down
onto cardboard or a styrofoam sheet to keep it from curling as it drys.
I let them dry overnight. Be careful not to touch or damage the emulsion
surface.
Sensitizing the Tissue
1. At this stage it is useful to keep the room light low.
Incandescent lamps are OK, but avoid flourescent lamps. I prefer to use
the yellow "bug lamps" as a light source.
2. Prepare a tray of sensitizer: Mix potassium dichromate with
distilled water (60 degrees F.) in a range of 1% to 6%. The relative
strength of this sensitizer was affect the contrast of the final print.
3% is a good starting point. Wear rubber gloves when dealing with the
potassium dichromate solution.
3. The now-dried tissue will be pre-soaked in distilled water at 60
degrees F. just long enough to make it lay mostly-flat. No more than 5
minutes.
4. When flat, transfer the pre-soaked tissue to the sensitizer tray
to remain in the potassium dichromate solution for 3 minutes at 60
degrees F. Very gently remove any air bubbles with a soft brush during
this 3 minutes.
5. Squeegee the sensitized tissue face down on a sheet of clean,
wetted glass.
6. Hang to dry in a dark room. Let dry for 1/2 to 1 hour, then turn
and rehand. When curling begins, pin the tissue to cardboard or
styrofoam sheet to maintain reasonable flatness.
7. Dried sensitized tissue can be stored in a sealed, light-tight
container for a mazimum of two weeks at 40-45 degrees F.
In an upcoming post, I will detail my methods for exposing,
processing and transfer from the tissue to the final support paper.
If there are questions, comments or horrified screams of
disagreement <g> please reply at your convenience. My skin is as think
as my head.
Bill Clark
wmclark@prairieweb.com
Scottsbluff Nebraska USA