Sealing cement

Ellen McCrady referred to research done in Japan on concrete, and
implications for the conservation of museum objects.  The article is
a short contribution to

    Toishi K.  and T. Kenjo: "Some aspects of the conservation of works of
    art in buildings of new concrete". Studies in Conservation, 20
    (1975), pp 118-122.

    **** Moderator's comments:   Thanks to Morten Ryhl who also sent
    in this citation

I have referred quite regularly to this and another article, by N.
Baer and P. Banks (Indoor Air Pollution:  Effects on Cultural and
Historical Materials in The International Journal of Museum
Management and Curatorship (1985) #4 pp 9-20). Jean Teatrault, at
the Canadian Conservation Institute also discusses (in his lectures)
the effects of aerosols liberated from concrete.  The alkaline air,
according to thee Toishi/Kenjo research affects new and old linseed
oil (yellowing), silk (losses in tensile strength), pigments and
glues to discolor, hair hygrometers lose their precision quickly,
etc.

Coatings have improved a great deal since this research was done,
and two-part epoxies have been known to either neutralize the
aerosol as it passes through, or block it.  A two-part epoxy is much
better than o one-part version for sealing.  High temperatures and
carbon dioxide help to speed curing of cement, so a building
occupied by many people is soon neutralized.

Housing collection materials in microclimates such as boxes and bags
helps a great deal to protect them from this and other
construction/environmental evils.

Lori van Handel
Director of Field Services/Assistant Conservator of Objects
Williamstown Art Conservation Center
Williamstown, MA 01267
413-458-5741
Fax: 413-458-2314

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                  Conservation DistList Instance 9:52
                  Distributed: Sunday, January 7, 1996
                        Message Id: cdl-9-52-005
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