Tom DeLay wrote in MMD 13.12.24, "I do not know about silicone spray
on paper, but I can tell you that any of that stuff sprayed on pouch
leather will shorten the life of the leather by decades."  He continued
to indicate having seen brush marks on leather where it has rotted away
after ten years.

I (Pete) have not tried any silicone spray, but when it comes to
sealing pouch leather with silicone (RTV #733 50-year window caulk), I
haven't seen any degradation in the leather with my samples made back
in July 2000, when I made samples of different types of sealers of
leather to see which ones worked best.

The sealer was swabbed on with Q-tips.  Pouches treated with the best
sealer that didn't change the feel of the leather were sealed with a
very thin layer of this silicone, and it sealed them completely with
two coatings.

I just took these same samples out (December 2013) to check if the
leather under the sealed silicone has any sign of rotting.  I see no
evidence in any of the samples having any issues at all.  Even tugging
on the leather it seems very stable and still seals 100%.

These samples have been inside one plastic bag with holes punched in
it.  All of the samples were stored in the same bag.  After over 13
years, I see no issues with using this thinned #733 RTV as a sealer.
If the silicone was an issue to the leather, at least one of the
samples would have had problems.

Pete Knobloch
Tempe, Arizona