Digital BW, The Print

Here is some info from the conservator at the Tate.

> There has been limited research carried out on Diasec mounting which
> suggests it is stable (silicone (the adhesive part - is a good durable
> material). It seems if the adhesive (or rather adhesion) fails it
> happens quickly, otherwise all signs are the process ages well -
> although the earliest examples of have seen are from the early nineties
> so there may be problems ahead. The most obvious drawback of any face
> mounting is the risk of scratching the surface. Shallow scratches can be
> removed but anything deep is permanent, with reprinting the only answer.
> There are of course benefits of the process  - I have longed believed
> that face mounting may well reduce susceptibility to fading - due to the
> low levels of oxygen reaching the dyes. Once again this needs to be
> tested.
>
> As you probably know Diasec is a licensed product available through
> limited outlets - but there are other forms of face mounting produced by
> rival companies. Only limited testing has been undertaken (all in the
> USA) on true Diasec - and virtually nothing on rival systems.
>
> The latest research into Diasec has been published in the American
> Institute of Conservation News journal. As far as I am aware this is the
> most comprehensive study of the durability of the Diasec process.
>
> AIC News, March 2002 Vol.27, No 2
> Written by Penichon & Juergens.
> I suggest you try and contact them for a copy - I think Martin Juergens
> has a website?

and here is some info from Martin Juergens:

In the case of a face-mounted Andreas Gursky photograph, there is a
high probability that the image was printed and mounted in
Duesseldorf at a specialist lab. This lab commonly uses a Plexiglas
with what they call 98% UV filter (but, during a visit, would not
further specify). The silicone rubber mounting system involved is a
licensed process named Diasec.

The maintenance of the immaculate Plexiglas surface may be somewhat
problematic. I have seen people at museums unconsciously (or
purposely) touch the surface of these prints, perhaps because in the
back of their minds they think it is glazing in a frame (so not so
bad!) and don't realize that it is actually the print's surface.

There has not been much too much research on these face-mounting
techniques and materials, but there are a few publications on the
subject:

    Penichon, S., Juergens, M., Murray, A. 2002.
    "Light and dark stability of laminated and face-mounted
    photographs: a preliminary investigation" in: Conference
    Proceedings, Works of Art on Paper--Books, Documents and
    Photographs, Techniques and Conservation, International
    Institute for Conservation (IIC), Baltimore, MD, pp. 154-159.

    Penichon, S., Juergens, M. 2002.
    "Issues in the conservation of contemporary photographs: the
    case of Diasec or face-mounting" in: AIC News, Vol. 27, No. 2,
    pp. 1, 3-4, 7-8.

    Penichon, S., Juergens, M. 2001.
    "Two finishing techniques for contemporary photographs" in:
    Topics in photographic preservation, Vol. 9, pp. 85-96.

Then there is a research project from the Master of Art Conservation
Program at Queen's University, Kingston, Ontario, which described
the mounting process and materials in detail and which I believe is
available at the CCI library (if not there, then surely at Queen's
University):

    Juergens, M. 2001.
    Silicone rubber face-mounting of photographs to poly(methyl
    methacrylate): process, structure, materials, and long-term dark
    stability.

To give you an idea of the contents of the IIC publication, here is
the abstract:

    The increasingly popular finishing techniques of laminating and
    face-mounting photographs and their effect on the long-term
    stability of the prints have not been extensively studied. In a
    preliminary investigation, colour photographs (unmounted,
    laminated, and face-mounted) were subjected to accelerated
    light- and dark-aging tests. In addition, samples of both
    un-mounted and face-mounted prints underwent quantification of
    acetic (ethanoic) acid off-gassing. Face-mounted photographs
    were more sensitive to light than unmounted ones but showed
    better dark stability. Laminates with ultraviolet inhibitors
    slowed the light-fading of the prints. Acetic acid is off-gassed
    by acetoxy-curing silicone rubbers used in face-mounting and
    escapes from the edges of the prints at a rate which is
    partially governed by storage temperature.

It should also be mentioned that prints mounted at different labs
had very different ageing results. The whole subject is pretty
complex, due to the variety of materials involved. We surely need
more research! Hope this helps"

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I'm checking to see if our Conservator has any of these publications tucked
away

tim a