Molds made of CASTALDO® LiquaCast® 0% shrinkage RTV molding rubber and similar compounds will last 2 to 4 years if properly stored away from heat, light and humidity. Exposure to atmospheric humidity will soften these molds and make them unusable.
Molds made of CASTALDO® LiquaCast® Long-Life and others made of true silicone rubber compounds such as CASTALDO® LiquaFast will NOT soften with age and are not degraded by atmospheric moisture and humidity.
Storage life depends on storage conditions, with dry environments prolonging mold life and humid environments shortening it. The life of cured molds can be prolonged by storage in air-conditioned rooms and in closed plastic containers such as those sold in food stores, for example Tupperware© containers. Even better are metal containers such as used cookie tins.
Store molds made of LiquaCast® and similiar compounds away from molds made of any other type of rubber. Adverse chemical reactions may occur that will shorten the life of all the molds involved.
To protect storage containers and storage areas from molds that eventually will soften, wrap them in kitchen wax paper. Some stores sell wax paper bags that are useful for this purpose. The residue left by softened molds can be cleaned by rubbing with a paper towel or clean cloth soaked in alcohol.
Desiccant packages of the type commonly sold with cameras and electronic devises are useful in drying the air inside closed containers and will prolong storage life. Bulk desiccants – typically blue pellets that turn pink in the presence of moisture – can be purchased from industrial supply houses and on the internet. They are often sold for drying damp closets and basements. A common chemical component is “silica gel” although other materials also work.
Below are photos of some desiccants that are widely available on the Internet and at hardware and home supply dealers...