C. Michael McKinney, MFA (mckinnm@host1.swosu.edu)
Mon, 22 Feb 1999 14:18:30 -0600
The following chemicals are used in radiographic film processing, though I
do not know formulas, etc. I only know this as I have to do the hazmat and
MSDS sheets for both darkrooms, mine and the radiology department's.
Developer
reducing agents: phendione, hydroquinone; activator: sodium carbonate;
restrainer: potassium bromide; preservative: sodium sulfite; hardener:
glutoraldehyde; solvent: water
Fixer
clearing agent: ammonium thiosulfate; activator: acetic acid; hardener:
potassium alum; preservative sodium sulfite; solvent: water
These are for automatic processors that run about 90 seconds. 20-25 sec in
Developer and 20 sec in fixer, 20 sec in wash and 25-30 sec in dry
I know that one text I used to come up with these chemicals indicated that
in manual processing, metol (Kodak Elon) was used in place of Phenidone.
The hydroquinone would be used to slowly reduce silver and produce heavy
density. The phenidone and hydroquinone mixed together it greatly enhances
reduction.
The action of the reducing agents is enhanced by maintaing the developer in
alkaline range of pH 10.0 - 10.5 with the activator, sodium carbonate.
Potassium carbonate, sodium hydroxide, and potassium hydroxide may also be
used. One could probably get away from the hardener, glutaraldehyde, since
this is primarily required to offset the roller transport abrasion.
Hope this helps. Also, if the film is exposed to light after development
and before fixing, then the unreduced silver hallides will be converted to
black silver.
TTFN
Michael
C. Michael McKinney, MFA
Southwestern Oklahoma State University
http://www.swosu.edu/~mckinnm
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