Memory foam is polyurethane with additional chemicals increasing its viscosity and density. It is often referred to as "visco-elastic" polyurethane foam, or low-resilience polyurethane foam.
Higher-density memory foam softens in reaction to body heat, allowing
it to mold to a warm body in a few minutes. A lower-density memory foam
is pressure-sensitive and molds quickly to the shape of a body pressing
against it, returning to its original shape once the pressure is removed
Visco-Elastic Memory Foam was originally developed by
