Re: T55 Se toner, was RE: POP process

From: Richard Knoppow ^lt;>
Date: 11/09/04-06:36:24 AM Z
Message-id: <>

-----Original Message-----
From: "Breukel, C. (HKG)" <>
Sent: Nov 9, 2004 3:46 AM
To: "''" <>
Subject: T55 Se toner, was RE: POP process

> -----Original Message-----
> From: Richard Knoppow []

> Kodak T-55 is a type of Selenium toner made with Sodium
> Sulfide. Some of the toning comes from the sulfide.


I do not believe that is correct, (unless boiling the stuff turns the
sulphite in Sulfide)

Anyway the recipe for T55 is:

Selenium toner bath Kodak T55 formula :

hot distilled water: 700 ml
anhydrous sodium sulfite : 150 g
selenium ( pulver) : 6 G
ammonium chloride :
 190 G
water to make : 1000 ml
 Add selenium and let boil 30 min. Filter to eliminate the residues, let
cool and add ammonium chloride. supplement with cold water to make one
For the use, a volume of this solution is diluted with 5 volumes of water.
The phototype is immersed lO to 15 min (@ 20C), then washed carefully
according to the conditions indicated in the preceding lines.

   Another thought. I am not sure what happens to the sulfite when boiled. KRST has Ammonium thiosulfate in it. I will let Ryuji figure out what chemical changes occur as the result of boiling. I will try to find the patent but I seem to think that the required boiling was very extended, maybe several hours or a day.
   As I said while its interesting to know the process I would not try to make the stuff.

Richard Knoppow
Los Angeles, CA, USA
Received on Tue Nov 9 06:36:32 2004

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