Traveling with liquid paints and art suppliesby aisling d'art ©2007
Are you traveling with paints, inks, or other liquid art media?
Carry all of your paints and liquids in ziplock bags as insurance against leaks. I like the bags that each have a slider thingie to open and close them.
Pack no more than one or two containers per baggie. It reduces the cleanup if one container leaks.
Be sure that no container is more than about 3/4 full, so that you have room for the air (and some paint) to rush out without losing paint in the process.
Seal each container as tightly as possible, so that the higher pressure inside the container doesn't cause the paint/medium/whatever to leak out en route.
Open each one carefully and slowly when you're at the higher altitude.
It's not a huge pressure difference, but it's enough that really full containers can slosh out.
If you have time, here's another tip: Gently warm your paint containers in a tray of very warm water, with the lids loose. When the contents of the containers has warmed, tighten each lid, and then take the container out of the water. As each container cools, the air inside will contract, making it less likely to go "pop" at the higher altitude. (You're sort of vacuum-packing your paints again.)
Just don't overheat the paints so that they change consistency or dry out!
[This was from one of my Yahoo Groups posts related to travel journaling.]