O.K., I was hoping to not have to go there. The solvent that the fibers are carried in evaporates inside the tire until the air in the tire is saturated with the solvent. Air outside the tire is not limited in volume and never reaches saturation.
Much like a container of water, if left uncovered it evaporates; if covered, it evaporates, condenses on the lid and sides, and then runs back to the bottom when the drops get big enough. Of course, the solvent that slime is in evaporates much faster than water!
>Hmmm. What's difference between outside air and inside the tire air,
besides
>pressure?