From: Richard Knoppow (dickburk@ix.netcom.com)
Date: 01/10/03-06:13:16 PM Z
----- Original Message -----
From: "John Glen" <microcrystals2002@yahoo.com>
To: <alt-photo-process-l@sask.usask.ca>
Sent: Friday, January 10, 2003 5:59 AM
Subject: A few questions about sizing and buffering...
> Hi All!
>
> A few questions about sizing and buffering.
>
> I have about a half Kg. of Kodak Balanced Alkali and I
> was wondering if it can be used to increase the pH of
> my BFK Rives paper I have... it is not quite as
> alkaline as I prefer....
>
> 1. What is Kodak Balanced Alkali mainly used for?
>
> 2. there is a number written after the ingredient
> (7775-19-1) is this the CAS # for sodium metaborate?
>
> 3. the label says air and moisture will reduce it's
> activity... how can I test to confirm that it is still
> "Fully" active...???
>
> 4. If Kodak Balanced Alkali can be used to buffer or
> increase pH, How would this be done? (What
> concentration & time?)
>
> 5. How else could this be done? (What chemicals,
> concentrations & times?)
>
> Thanks,
>
> John
>
Kodalk Or Kodalk Balanced Alkali is Sodium Metaborate,
although there is some question as to the water content. The
Kodak product is probably the pentahydrate.
It is a mixture of Borax and Sodium Hydroxide. There are a
couple of ways of making it but Kodak uses a once patented
method of fusing the two. It can be made by simply mixing
the two ingredients in water.
Sodium Metaborate is used in many developer formulas and
in fixing baths. It is somewhere between Borax and carbonate
in pH. It has the advantage over carbonate that when used in
developers it does not evolve gas when put into the stop
bath or into an acid fixing bath.
Kodak developer formulas with the prefix DK are made using
Kodalk. It is supposed to be a better buffer than carbonate.
Evidently, Kodak has always bought its metaborate from the
U.S. Borax Company, the makers of Twenty Mule Team Borax.
Sodium Metaborate is available as a pentahydrate and as an
octahydrate. There is also Potassium Metaborate but I don't
know much about it. Its found in the MSDS of a few packaged
photographic processing solutions.
I have no idea if it is suitable for your application.
--- Richard Knoppow Los Angeles, CA, USA dickburk@ix.netcom.com
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