D-76 and Boric Anhydride.

Thanks to the Analyst for replying to my question of Boric Anhydride in
D-76. However, if Kodak state that a certain chemical component is included
in a specific processing product in their MSDS then I have no reason to
doubt their word, after all why should such a reputable company deliberately
mislead their customers?
To go back to my original question, I was asking what the function of Boric
Acid has in D-76 and how does it differ from Boric Acid?
Now here is another question, if you think that the commercially packaged
Kodak developer is the D-76d formula, then why does the Kodak product
contain close to 110 grams of constituents per litre instead of 123 grams
that are in the D-76d formula?
Kodak are hardly going to reveal a company secret and I certainly don't
expect them to. I was simply asking about the function of Boric Anhydride in
Kodak D-76 and how does it differ to Boric Acid?
Does anybody out there actually know the answer besides a Kodak chemist?

On Mon, 27 Dec 2004 18:13:39 -0000, "Keith Tapscott" <not DeleteThis @home.com>
wrote:

*Thanks to the Analyst for replying to my question of Boric Anhydride in
*D-76. However, if Kodak state that a certain chemical component is included
*in a specific processing product in their MSDS then I have no reason to
*doubt their word, after all why should such a reputable company deliberately
*mislead their customers?

you wouldn't see the difference regardless of which components were
used. In solution most compounds exist in ionised form. Anhydride
means "less water". When you remove water from boric acid, you get
anhydride, or as we call it boric oxide. In my view, Kodak put boric
anhydride as a generic term for boric acid and borates.
I deal with MSDS on daily basis, and can assure you, thsoe documents
are worthless for chemists, we can make our own assessment. Laypeople
wouldn't have a clue to verify, if the MSDS is right or not.
Going back to your example of D76 - it has to be pH 9 or around to
work. Boric oxide will lower pH, hence some carbonate or hydroxide
needs to be added to compensate. from manufacturing point of view, it
does not make sense. Boraks is not hygroscopic like anhydride, it is
cheap.
If you believe Kodak is a reputable company, then good luck.

*To go back to my original question, I was asking what the function of Boric
*Acid has in D-76 and how does it differ from Boric Acid?

Some modified D76 formulations use a mixture of boraks and boric acid.
Such develeoper has slightly lower pH, it is less active, but also
exhibit less changes when developer is reused (better buffering).

*Now here is another question, if you think that the commercially packaged
*Kodak developer is the D-76d formula, then why does the Kodak product
*contain close to 110 grams of constituents per litre instead of 123 grams
*that are in the D-76d formula?

You assume anhydrous salts, which may not be the case. i cannot answer
for Kodak, the only way would be to analyse it. Compare dev times, do
they match D76 or D76d? In my view, commercial D76 from Kodak equates
D76 from formulae. Kodak put boraks into bags, not boric oxide, end of
story. If you believe otherwise, sorry i cannot help.

*Kodak are hardly going to reveal a company secret and I certainly don't
*expect them to.

That secret is no secret for over 70 years.

* I was simply asking about the function of Boric Anhydride in
*Kodak D-76 and how does it differ to Boric Acid?

There is no boric anhydride in Kodak D76.
In solution boric anhydride react with water forming boric acid.
For all practical purposes, they would be equivalent.

*Does anybody out there actually know the answer besides a Kodak chemist?
Any chemist understanding inorganic chemistry.
Ilford, Agfa, and many other independent manufacturers.

Stop treating MSDS like Bible or any other holly book.
*