Blueprints

Tanya Faulkner <tanyafaulkner [at] rogers__com> writes

>... I am looking for a good source on the treatment of cyanotypes
>but have yet to come across a valuable resource.  I would greatly
>appreciate recommendations of credible sources on the care and
>conservation of cyanotypes.

You need to read Mike Ware's book

    Mike Ware:
    Cyanotype: The history, science and art of photographic printing
    in Prussian blue, 1999. West Yorkshire, Science Museum and
    National Museum of Photography, Film and Television
    ISBN 1-900747-07 3)

And here's some information on the preservation and treatment of a
water-damaged blueprint that Julia Landry received from Mike Ware in
2001 and kindly sent on to me:

   "There are at least three causes for the loss of Prussian blue
    (see my book on Cyanotype - details below):

        1.  fading by light (reversible in dark)
        2.  bleaching by alkali (restored by acid if recent)
        3.  washing out by water (irreversible)

   "In your case, it sounds like (3) mostly.

    >Question 1
    >
    >Is there anything that I can use that will restore some of the
    >blue and make the lines more legible and, if so, how long does
    >the effect last?

   "If the pigment has been lost there is nothing I can recommend to
    restore it.

    >Question 2
    >
    >Will I do any harm if I immerse it in a distilled water bath to
    >try and lessen some of the tidemarks and generally clean it up a
    >bit?

   "In principle, any aqueous treatment will tend to remove some
    more Prussian blue, which is easily dispersed. However, the loss
    should be imperceptible if you use distilled water at pH about 6
    to 6.5, for no more than 20 minutes, at room temperature.

   "Good wishes,
    Mike (Dr Michael J Ware)"

Tanya--You should also also check out:

    Eleonore Kissel and Erin Vigneau.
    Architectural Reproductions:  A Manual for Identification and
    Care (1999, New Castle, Oak Knoll Press
    ISBN 1-884718-62 0)

Karen Potje
Head, Conservation/Preservation
Canadian Centre for Architecture


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                  Conservation DistList Instance 19:26
                Distributed: Saturday, November 19, 2005
                       Message Id: cdl-19-26-009
                                  ***