Heat and oil paintings

I am an oil painter, and am looking for insight into the archival
risks of heat on oil paintings. When painting on location, paintings
are frequently left in the car. Temperatures can be high, especially
in mountain environments with intense sun heating up the car
interior. Paintings left in a hot car could be easily exposed to
temps over 120 deg F. This also happens when traveling with finished
paintings to shows in summer months.

My question is this: How much damage is this doing to the oil
paintings? Are oil paintings on board (acrylic primed untempered
"masonite") less susceptible to damage than oil paintings on canvas
or linen, especially glue-sized fabrics? And how much heat exposure
is a serious concern? (Is 4 hours okay? Would a painting left for 4
days in a hot car be a problem down the road for a collector?)

Diana Moses Botkin
Art for a Lifetime
HC 60, Box 198
Bonners Ferry, ID 83805
208-267-0650


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                  Conservation DistList Instance 19:10
                Distributed: Wednesday, August 17, 2005
                       Message Id: cdl-19-10-030
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