Deterioration of color microfiche

Anita Shaughnessy <anita.shaughnessy [at] mvs__udel__edu> writes

>We have some color microfiche that is developing a pinkish hue. As I
>understand it this is an inherent problem with color film, and the
>only way to stop it is cold storage.

The following is posted on behalf of Margaret Hey who is not on the
list.

Some suggestions:

    1.  Read Henry Wilhelm's book, and in particular pages 6, 218
        and 219 where he discusses the color stability of
        micrographic film. He concludes (and is supported by work
        from the Image Permanence Institute [Microform Review,
        21(4), 1992, 142-143]) that Ilford Ilfochrome Micrographic
        films are the most satisfactory being (to quote)'essentially
        permanent at dark storage at room temperature'. The reason
        for this lies in the P-5 process used, which is still under
        Patent to Ilford (i.e. no-one else can use the process).

    2.  As your microfiche is only a commercial product which can be
        re-purchased it does not warrant the expense of color
        restoration which could be used on valuable artifacts.

    3.  By all means purchase another microfiche BUT unless you and
        your successors wish to repeat the process at 15 year
        intervals, insist that the duplicate be produced on
        Ilfochrome duplicating film (see below) unless, of course,
        the Master has also already faded in which case you might as
        well stick with what you have.

    4.  Two types of Ilford film are available--camera negative and
        duplicating, all on polyester base, 4mil and 7mil
        thicknesses, roll and sheet form.

        Camera negative roll film is:
            Ilfochrome Micrographic CMMF4 3.5 x 30m RKS30 E1 DPP
        Duplicating roll film is:
            Ilfochrome Micrographic 1M CMP F4 3.5 x 30m E1 DPP

    5.  I obtained this information on Nov 27 from the London Head
        Office who told me that the film is stocked in Switzerland
        even if not in all Ilford agencies world-wide so there
        should be no problem in obtaining it.

These films are more expensive than other micrographic color
products but film cost is only a tiny proportion of microfilming
expenses. Besides, initial expense but lasting hundreds of years
against lower expense repeated every 15 years: is there a decision
to be taken?

Surely we should always insist on quality film if we are not to have
to repeat processing at distressingly short intervals of time?

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                  Conservation DistList Instance 10:52
                Distributed: Wednesday, December 4, 1996
                       Message Id: cdl-10-52-009
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