Manganesed Phospholene #7

Lara Kaplan <larakaplan [at] hotmail__com> writes

>I am examining and treating a group of archaeological metals treated
>in the 1960's with the rust remover and corrosion inhibitor
>Manganesed Phospholene #7 (Western Reserve Laboratories, Cleveland
>OH), a proprietary product that saw some use in the past and is
>still manufactured and used today. Some of the artifacts in the
>group have remained stable, however others are corroding. With the
>awareness that there are many factors at work such as surface
>coatings, changing environmental conditions, etc., it would still be
>helpful to know more about the mechanisms of this product to better
>understand its effects. Has anyone researched or used this product,
>or encountered collections on which it was used?

We used MP-7 back in the 1980's on a large steam engine project
based on recommendations from someone at Lawrence Livermore labs. It
was then manufactured by the Coulter Company (Georgia?), then by the
"Must for Rust Company" in Cedar Ridge California.  My understanding
is that it is simply a phosphoric acid solution, which an MSDS from
Milano Inc <URL:http://www.milanco.com/msds/MSDS/mp7.htm> confirms.
Another product made by Pantheon Chemical (see
<URL:http://www.mp7.com>) is *not* the same material.


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                  Conservation DistList Instance 16:74
                   Distributed: Tuesday, May 27, 2003
                       Message Id: cdl-16-74-003
                                  ***