A good way to think of what happens with any of the treatment
materials and vacuum, Kelly, is that when you cover the material
with the treatment goo and subject it to a vacuum the air in the
porous places expands and bubbles out. Then when you release the
vacuum the atmospheric pressure forces the goo into the crevices
where the air had been. Depending on the degreee of vacuum, you
replace 1/2 to 90+% of the air. You can do a lot with just the suck
from a vacuum cleaner rigged to some kind of a chamber. Not a very
"industrial" job at all, just a wonderful "appropriate technology"
use of physics!