The DARKROOM COOKBOOK, Third Edition

174 THE DARKROOM COOKBOOK
Uses: As a preservative in photographic emulsions; concentrated developers; rapid drying
and cleaning.
Notes: 40% alcohol is the equivalent of 40% by volume or 80 proof alcohol.
Caution: Infl ammable.
ALCOHOL, ISOPROPYL
Synonyms: Dimethylcarbinol, Isopropanol, Secondary propyl alcohol.
Appearance: Colorless liquid; weak alcoholic odor resembling that of acetone.
Uses: In developing formulas for its high solvent properties. To replace alcohol wherever it is
called for. To control the diffusion of solutions into emulsions.
Caution: Infl ammable.
ALCOHOL, METHYL
Synonyms: Carbinol, Colonial spirit, Columbian spirits, Methyl hydrate, Methylic alcohol,
Methanol, Pyroligneous spirit, Pyroxylic spirit, Wood alcohol, Wood naphtha.
Appearance: Clear, colorless, mobile liquid.
Uses: For denaturing ethyl alcohol; solvent; in preparing very concentrated solutions of developers;
cleaning prints and negatives; to control diffusion of solutions into emulsions; the making
of fi lm cement.
Caution: Burns with a non-illuminating fl ame. The presence of excessive amounts of methyl
alcohol may cause softening of the fi lm base.
ALCOHOL, TERTIARY BUTYL
Synonyms: Trimethylcarbinol, Tertiary isobutyl alcohol, Tertiary butyl alcohol.
Appearance: Colorless crystals, camphor color. Melts at 78F/26C to a colorless, viscid liquid.
Uses: Film cleaner.
ALUM (see Alum, ammonia; Alum, chrome, potassium; Alum, potassium; and Aluminum sulfate)
ALUM, AMMONIA
Synonyms: Alum, Aluminum-ammonia sulfate, Ammonium alum.
Appearance: Colorless crystals or white powder; styptic taste.
Uses: In fi xing baths; hypo-alum (sulfi de) toning; hardener for gelatin.
ALUM, CHROME, POTASSIUM
Synonyms: Chrome alum, Chromium and potassium sulfate, Potassium chromium sulfate.
Appearance: Dark violet-red crystals (ruby red by transmitted light); or light violet powder.
Uses: Preparation of chrome alum fi xing bath; as hardening agent for gelatin.
ALUM, IRON
Synonyms: Ammonio-ferric alum, Ammonio-ferric sulfate, Ammonium sulfate, Ferric ammonium
alum, Ferric ammonium sulfate, Ferric alum, Iron ammonia sulfate, Iron ammonium alum,
Iron sulfate.
Appearance: Violet effl orescent crystals.
Uses: In reducer formulas; toning solutions; sensitizing solutions.