When you release the liquid carbon dioxide from the tank, the expansion of the liquid and the high-speed evaporation of carbon dioxide gas cools the remainder of the liquid down to the freezing point, where it turns directly into a solid.
Quick Answer. Cigars stay fresh without a humidor for up to a month when kept in their original wrapper. Cigars kept in a humidor can last for years in a properly controlled environment. A humidor keeps cigars from drying out and the oils from evaporating. Keep Learning.
Paper exposed to air doesn't last long. Paper stored in dry nitrogen can last centuries. DVD-R should last close to 100 years if it's kept somewhere dark, but it hasn't been around long enough to tell. Pressed disks should last a lot longer.