Re: Kodalith fine line developer formula (sort of)

From: Nick Zentena <zentena@sympatico.ca>
Subject: Re: Kodalith fine line developer formula (sort of)
Date: Tue, 23 Nov 2004 10:53:22 -0500

> Okay. So the developers that leave out both are no worse then
> those that contain them. The formaldehyde binds the sulfite. The
> sulfite doesn't provide anything to the Lith effect. OTOH the Lith
> formulas that contain just the sulfite should be avoided.

Formaldehyde and sulfite do not make free sulfite to be zero. They
make an equilibrium working as a sulfite buffer, amounting free
sulfite to equivalent of a couple of grams per liter. I have posted a
developer calle "Burning Lithprint developer" in old pure-silver list,
which contains a couple grams of sulfite, bromide and hydroquinone, in
a solution buffered with trisodium phosphate. It's a very active
developer for lith printing, but has very short life unless a gram of
sulfite is added periodically, because of no sulfite reservoir. Yet I
can get a few prints out of each liter of the solution. The idea is to
have active solution ready for one-shot use to eliminate the guesswork
associated with old brown.

Hydroquinone-only classic lith developers are becoming
obsolete. Modern lith film/developer system use contrast enhancing
agents (hydrazine compounds) for true infectious development. But then
lithographic films are getting obsolete as well.

--
Ryuji Suzuki
"People seldom do what they believe in.  They do what is convenient,
then repent." (Bob Dylan, Brownsville Girl, 1986)