Science of foam making
I’m often asked about how our foams are made. The seats in your car, office chair, pillows, couch and of course, mattress are most likely made from a polyurethane foam.
What is Polyurethane Foam?
Polyurethane foam is made from raw, liquid polyurethane. It’s comprised of two chemicals which, when mixed and heated, form liquid polyurethane prior to being further processed. These chemicals are polyol, a type of complex alcohol, and diisocyanate, a petroleum byproduct that reacts with alcohol. By combining the two, a stable long-chain molecule is formed. It's a polymer, or plastic, known as urethane.
How is Polyurethane Foam Made?
Once the two ingredients have been combined to form hot liquid polyurethane, they are passed down through a pipe into a nozzle head. Beneath the head is a series of rollers upon which waxed paper passes by. The nozzle jets a fine spray of hot liquid over the waxed paper, mixing with blasts of carbon dioxide coming from another nozzle. This causes the polyurethane to expand as it moves down the conveyor belt, forming a foam strip. The edges of the foam are trimmed and compressed to ensure it retains a viable shape. The foam is comprised of an untold number of tiny gas bubbles trapped in the polyurethane. Unless the gas is released, the foam will take on the consistency of a rock. So, the foam passes beneath a series of heat lamps. It dries the foam and causes the bubbles to expand, then burst, leaving a completed spongy porous material behind. The block of foam will now need to cure for about 48 hours where it will then be further processed into its final shape. This shape can be in the form of pillows, cushions for couches or mattress toppers or cores.
What is Polyurethane Foam Used For?
Polyurethane foam is used primarily for bedding and furniture stuffing. It's hypoallergenic, nontoxic and does not degrade over time. This means that cushions filled with it will always regain their shape, no matter what punishment they're put through. It’s uses are in the furniture, bedding auto and marine industries. The center core or backbone of Bill’s Bed is a 7” polyurethane core.