Re: Cianotypes

John Rudiak (wizard@laplaza.taos.nm.us)
Wed, 8 May 1996 23:32:43 -0600 (MDT)

On Thu, 9 May 1996, Alan Kleiman wrote:

>
>
> Does somenone know the reaction that ocures in the cianotype proces?
>
>
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> Alan Kleiman
> akleiman@infoabc.com
>
>
The paper is coated with a mixture of ferric ammonium citrate and
potassium ferricyanide. Exposure to light reduces the ferric salt to its
ferrous state, and when the print is placed in water, ferro-ferricyanide,
or prussian blue is formed as a result of the reaction between the
ferrous salt and the ferricyanide, the water being the vehicle, or agent
providing the environment where the reaction can occur.

Hope this answers your question.

John