garethdavies486
"PYROCAT-P" the raw chemicals.
These are the raw chemicals for making PYROCAT-P film developer.From L>R sodium hydrogen sulphite:4-aminophenol hydrochloride:pyrocatechol:potassium carbonate.PYROCAT developers originally formulated by Sandy King. {I made the 4-aminophenol hydrochloride myself by hydrochloric acid hydrolysis of paracetamol. Unlike 4-aminophenol free-base, the hydrochloride is stable to the atmosphere. There seems to be an awful amount of confusion amongst photographers regarding the difference between 4-aminophenol (free base) and 4-aminophenol hydrochloride. The difference is SIMPLE to comprehend...the hydrochloride is simply the free base chemically combined with hydrogen chloride. It is an ionic compound formulated simply as [C6H8NO]+[Cl]- It is very soluble in water and when silver nitrate solution is added to the solution a thick white precipitate of silver chloride forms instantly. If anyone wants further information or clarification let me know!
"PYROCAT-P" the raw chemicals.
These are the raw chemicals for making PYROCAT-P film developer.From L>R sodium hydrogen sulphite:4-aminophenol hydrochloride:pyrocatechol:potassium carbonate.PYROCAT developers originally formulated by Sandy King. {I made the 4-aminophenol hydrochloride myself by hydrochloric acid hydrolysis of paracetamol. Unlike 4-aminophenol free-base, the hydrochloride is stable to the atmosphere. There seems to be an awful amount of confusion amongst photographers regarding the difference between 4-aminophenol (free base) and 4-aminophenol hydrochloride. The difference is SIMPLE to comprehend...the hydrochloride is simply the free base chemically combined with hydrogen chloride. It is an ionic compound formulated simply as [C6H8NO]+[Cl]- It is very soluble in water and when silver nitrate solution is added to the solution a thick white precipitate of silver chloride forms instantly. If anyone wants further information or clarification let me know!