UV filters

Jeanne Drewes <jdrewes<-a t->jhu< . >edu> writes

>I am looking for recommendations for uv protection for glass on
>table cases.

In our museum we use UV films filters for the last nine to ten
years. They prove to be a very effective in reducing U.V (nearly
95%) from the natural light sources.

This product, CL - 400 -X, is produced by Madico(r) L.T.D. This
product is very durable and after quite a relative long time did not
show any significant change in its properties as transparency, color
and eliminating UV radiation, and we have not noticed any structural
cracks or splits.

This is a considerable advantage to the product quality as it is
daily exposed to rough climate conditions in summer outdoor
temperature can reach 100-105 deg F. and in winter 32-28 deg F. most
of the year the natural light radiation is considerable high
2500-2700 lux.

The film is placed on the window facing indoor and is
first wet by water which activates its acrylic glue (this is the
only information concerning the glue properties we could get, the glue
chemical properties are considered an industrial secret by the
producers), then it is placed on the window or showcase to dry for
few hours (solvents as MEK or acetone can be used to remove the
film). It is recommended that an experience technician would do
the job to achieve best results.

Here are some additional properties
of this product:

    Visible light transmission:     85%
    UV light transmission:          0-4%
    Film thickness:                 0.004
    Structure:                      single ply
    Tensile strength:               100 pound per inch
    Adhesive type:                  acrylic resin
    Peal strength:                  4-5 pounds per inch

Another important fact to consider: the film protects from any
possible glass damages in case the glass breaks or cracks. We feel
this product should be highly recommended for reducing UV radiation.

Michael Maggen
Senior paper Conservator
The Israel Museum Jerusalem
Israel

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                  Conservation DistList Instance 11:14
                 Distributed: Wednesday, August 6, 1997
                       Message Id: cdl-11-14-001
                                  ***