Re: T55 Se toner, was RE: POP process

-----Original Message-----
From: "Breukel, C. (HKG)" <C.Breukel@lumc.nl>
Sent: Nov 9, 2004 3:46 AM
To: "'alt-photo-process-l@sask.usask.ca'" <alt-photo-process-l@sask.usask.ca>
Subject: T55 Se toner, was RE: POP process

> -----Original Message-----
> From: Richard Knoppow [mailto:dickburk@ix.netcom.com]

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

Richard,

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
liter.
For the use, a volume of this solution is diluted with 5 volumes of water.
The phototype is immersed lO to 15 min (@ 20°C), 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
dickburk@ix.netcom.com
Los Angeles, CA, USA
Received on Tue Nov 9 06:36:32 2004