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Subject: Picric acid danger Glue sticks Microfiche, enclosures and ANSI standards

Picric acid danger Glue sticks Microfiche, enclosures and ANSI standards

From: Doug Nishimura <dwnpph>
Date: Friday, April 26, 1991
Anyway, I just had a peek to see if I could help you locate
the picric acid comments.  No wonder you don't remember it -
it's dated 9/22/88 and was from one of the "annual" collections
(I had requested it to catch up with things since I had only joined
about a year ago.)

    **** Moderator's comments:   here is the item in question, which is
    in Year2.dst:

        Spot test for collagen:  place particle in a drop of FUCHSIN and
        PICRIC ACID.  Soak for 1 minute, rinse with water droplets until
        clear.  Collagen will stain deep red.  (From Raff, Leather Cons.
        News.  citation on request.)

The mixture you mentioned for collagen spot testing was fuchsin and
picric acid.  All the bottles of picric acid that I've worked with had
several inches of water on top.  Merck says: "Keep in a cool place and
remote from fire. Explodes when rapidly heated or by percussion!
Incompat: All oxidizable substances, albumin, gelatin, alkaloids. Note:
For safety in transportation, 10-20% water is usually added."

As a short catch up note, I remember seeing a number of postings about
glue sticks.  We had tested tested the effects of a number of glue
sticks on photographic materials during the development of the PAT
(Photographic Activity Test) in ANSI IT9.2-1990.  Something in the glue
sticks tested was quite aggressive.  Mainly there seemed to be a
non-homogeneous component causing localized attack on the silver

Re: microfiche, enclosures and the ANSI standards:

a) individual enclosures do help, but the advantage may not be as
noticeable in heavily used collections.  Often physical damage is so
much worse than anything related to storage that the enclosure (or
number of fiche per envelope) doesn't matter.  However, for purists, the
point of an envelope is to provide individual protection for the object.

b)  Note that the enclosure used should meet the requirements of ANSI
IT9.2-1990.  This is the enclosure standard for photographic materials.

c) The ANSI standard frequently quoted in library manuals and standards
is for storage copies only.  Use copies are not included in the standard
because of the added problem of physical abuse.  However, all other
things being equal, storage (and use) under the conditions given for
optimum storage should help to promote optimum life even in use copies.
However, if the storage and use environments are too different then the
fluctuations caused by removing and returning the fiche into storage may
cause worse degradation problems.

d) ANSI is changing the storage standard (expect the new standard
available in late 1991 or early 1992).  At the May meeting in Ottawa,
the IT9 committee approved a number of changes including:

    1) Recommended storage humidity lowered to 20-30% RH. Although this
       may cause the gelatin to be more brittle, and shrink, studies on
       rabbit glues, gelatins and related materials seem to  show that
       gelatin can handle quite a bit of tensile stress.  In addition,
       storage copies are not expected to see much handling and
       therefore brittleness is not expected to be a problem.

       This change (from the original 15 to 50% RH recommendation) has
       occurred because of the amount of data that shows that gelatin
       lasts longer under lower humidity, the gelatin "closes up" and
       protects the silver much better under lower humidity, dyes last
       longer under lower humidity and the film support (particularly
       acetates) last much longer under lower humidity. Data from the
       safety film project here at IPI, have shown that the benefits of
       low humidity storage are far more significant than was once
       thought.  The IT9 committee looked at the data and agreed that
       the benefit seemed to outweigh the added cost of improved
       dehumidification that the film storage standard was revised.

    2) The terms "medium term", "long term" and "archival" have been
       removed from the text and replaced by "LE" numbers.  The LE
       numbers are very conservative Life Expectancy numbers.

                  Conservation DistList Instance 4:56
                  Distributed: Sunday, April 28, 1991
                        Message Id: cdl-4-56-009
Received on Friday, 26 April, 1991

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