Quote Originally Posted by c6h6o3 View Post
I think the recent association of 'pyro' with catechol in its many guises is purely the result of Sandy King's choice of name for the groundbreaking developer he invented.

Gerald: I will henceforth excise the word 'pyrocatechin' from my vocabulary. I place that misnomer in the same class as calling a substance as alkaline as pyrogallol 'pyrogallic acid', which some vendors still do.
Pyrocatechin is rarely used these days for catechol, but pyrocatechol is a perfectly good modern equivalent, and in some respects has more use in the scientific literature.

When I developed the Pyrocat formula I used the name Pyro in it because whether you call the chemical pyrocatechin, pyrocatechol, or just catechol it does the same thing in development as pyrogallol, i.e. it stains and tans when used in solutions low in sulfite.

I would also note that in The Film Developing Cookbook, Anchell and Troop treat both pyrogallol and pyrocatechin in the same chapter, Tanning Developers.

That said, I find it perfectly reasonable to use the term "pyro developer" to refer to either pyrogallol or pyrocatechol.

Sandy