Latex balloons are made from latex rubber, a naturally elastic material used to make everything from latex house paint to latex gloves. In the case of balloons, the rubber is molded into various shapes and ordinary air, or other gases such as helium, can be forced into them for expansion purposes.
Latex balloons begin life as special metal molds and a vat of liquefied latex rubber. The bulb-shaped molds are lined up in single file along a conveyor belt system. At the lowest end of the conveyor belt, the molds dip into the vat of latex and emerge with a thin coating of rubber. As the series of molds moves through the air, the latex dries and cures. A machine rolls one end of the balloon just before a controlled puff of air blows it off the mold. This rolled end allows users to inflate the balloon more easily.
After opening a package of these balloons, a user can either inflate an individual balloon by blowing air into it with his or her lungs, or by attaching it to a special canister filled with compressed air or helium. It may be helpful to stretch the uninflated balloon several times in order to reduce the amount of pressure necessary to blow it up. Latex balloons can be inflated to many times their original size, but over-inflation often leads to an explosive burst.
Unlike the Mylar or foil balloons often seen at parties, latex balloons can be stretched and manipulated into various shapes by skilled balloon artists. Long, thin latex-based balloons are usually twisted into animal shapes, flowers or even party hats by professional clowns hired for birthday parties. Traditional round balloons filled with helium may be used to form colorful bouquets or given out as treats for party guests.
Those with a sensitivity to latex or neoprene may not want to handle latex balloons directly, since the contact may trigger a reaction. Sometimes the interior of a balloon will have a powdery coating, but the powder is actually cornstarch or other non-toxic substance used as a mold releasing agent at the manufacturing plant.
Latex balloons filled with helium are often released into the air during festive occasions, but this practice is not always friendly to the environment. Once the balloons reach a certain altitude, their internal pressure becomes greater than the external atmosphere and they will eventually pop. The latex remnants can cause problems for waterfowl and other animals which may ingest them, which is why many cities now restrict or regulate any large-scale latex balloon launches.