-----Original Message-----
From: Ryuji Suzuki <rs@xxxxxxxxxxxxxxx>
Sent: Apr 5, 2005 1:20 AM
To: pure-silver@xxxxxxxxxxxxx
Subject: [pure-silver] Re: Toning VC Papers..Update
From: "Richard Knoppow" <dickburk@xxxxxxxxxxxxx>
Subject: [pure-silver] Re: Toning VC Papers..Update
Date: Sat, 2 Apr 2005 14:56:21 -0800
> From: "J.R. Stewart" <jrstewart@xxxxxxxxxxxx>
> To: <pure-silver@xxxxxxxxxxxxx>
> Sent: Saturday, April 02, 2005 10:53 AM
> Subject: [pure-silver] Re: Toning VC Papers..Update
> > Any comment on why I would smell the ammonia smell in dilute KRST
> > when adding Na Carbonate to the KRST solution?
> I can't explain the odor. KRST contains some Ammonium
> Thiosulfate. I have never seen a pH for the toner.
The odor is ammonia released by increased pH. KRST contains ammonium
ion in the form of ammonium thiosulfate.
> > know how long it takes alkali to soften the emulsion such that it
> > aids toning, but I placed the print directly from the wash water
> > into the KRST containing NaCarbonate and the tone emerged pretty
> > quickly (less than 3 minutes, probably more like 2-- Compared to
> > more than 15 minutes without the NaCarbonate.
I don't think the "softening" is much of a factor here. It may simply
increase the dry down effect.
> Ryuji Suzuki tested at least one of these formulas recently
> and reported it resulted in an immediate orange stain. I
> mention this because of the added alkali. I don't know why
> it was added.
I never attributed the orange stain or any precipitate to the added
alkali. My best guess is that the thiosulfate in the KRST is involved
in this orange stain and/or sulfur precipitation problem.
Perhaps my wording was not clear. I meant that you had reported the
formulas for combining KBT and KRST didn't work, not that the carbonate or
metaborate was a factor.
> A mystery: When Kodak was still making Ektonol print
> developer one of its features was that it didn't cause
> staining during toning because it was carbonate free. I have
> no idea what this was about and no one at Kodak could give
> me any information. Ektonal is still available as a liquid
> concentrate as Ektaflo Type-2 (Ektaflo Type-1 was liquid
> Dektol and is now called Polymax Developer). Ektonol
> contained Borax and Sodium Hydroxide, which form Sodium
> metaborate (Kodalk) in solution. It may be worth trying this
> stuff if nothing else works to eliminate staining.
I doubt it. Carbonate washes out very fast. If you give adequate
rinsing after fix and before toning and still get stain, that's not
because of carbonate residue in the coated layer. If Ektonal does
something differently, it's probably something else.
Indeed, I routinely add carbonate to polysulfide solution and have no
problem with staining.
I have no idea of what staining Kodak was refering to, or what toner caused
it. I've never encountered staining which could be attributed to the
developer. However, something led Kodak to make this statement about Ektonol,
so I mentioned it.
--
Ryuji Suzuki
--
Richard Knoppow
dickburk@xxxxxxxxxxxxx
Los Angeles, CA, USA
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