RE: plea to chemists

From: Dane Johnson ^lt;>
Date: 11/11/05-08:47:24 PM Z
Message-id: <>


Try contacting Dr. Robert Chapman through Photo Techniques magazine
( for some solid chemistry information.
He periodically authors the Photochemistry column for the magazine.

According to the Jan/Feb 2005 issue: Contributing Editor Robert
Chapman holds a Ph.D. in chemistry from Yale University. He has
worked in photo research and development departments of DuPont
and Unicolor, and spent many years exploring the photochemistry
of holography. Currently, he is an independent photochemistry
consultant and a professor at Eastern Michigan University.

Thus, he can probably be contacted either through the editors
of Photo Techniques magazine or Eastern Michigan University.

Good Luck!

Dane Johnson

>--- Original Message ---
>From: "Christina Z. Anderson" <>
>To: Alt List <>
>Date: 11/10/05 5:47:55 PM
For the first time since I started teaching Experimental Photography,
>and Risk Management has more or less told me today that I can
no longer
>teach the mordancage process because of the chance of toxic
gas, etc.
>I have talked with 6 different chemists over the last three
weeks about
>whether toxic gas is released with the process. None of them
have said so.
>But Safety and Risk Management does.
>I am NOT pouring glacial acetic acid directly on copper chloride.
Here is
>the formula:
>Into 750 ml water pour 80ml glacial acetic acid.
>Add 30g copper chloride and stir.
>Add water to 1000ml..
>At time of use, this "Part A" is mixed in equal amounts with
20v hydrogen
>peroxide. The print is submerged in this for a few minutes,
rinsed (but not
>always well) and then redeveloped into developer or toner, such
as thiourea
>or sepia.
>The last person I talked to said that in the dilution I am using,
the acetic
>acid will reduce the copper chloride to a salt, not a toxic
gas (e.g.
>What do you chemists think?? Jon Bailey, Judy Siegel, etc.,
you've taught
>this process before; what do you know?
>The students are very unhappy at this turn of events, as you
can imagine.
>But I would not want to teach something that has this kind of
danger to
>students, either. So I really need to know the bottom line here...and
it is
>frustrating that there is conflicting information between chemists
>Safety and Risk Management. That said, SRM is the final word,
so I would
>have to convince them they are wrong.
>I just don't have any close chemist friends short of this list
>Thanks in advance,
Received on Fri Nov 11 20:47:20 2005

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