~Comfort and Durability as functions of Firmness and Density~
A frequently heard term when discussing PU foam is “I want that really firm density”.
The truth of the matter is the quality and durability is derived from the density; how much chemical is utilized in making a cubic foot (cu ft) of foam. The higher the density the more durable the foam; up to a point. Long term testing has determined that 1.8 lbs/cu ft density, provides the best balance between fatigue resistance and chemical/foam cost. Improvements in longevity performance are minimal at higher densities when dealing with conventional foam. Firmness of foam (IFD) (Indentation Force Deflection) can be adjusted in the process to achieve similar hardness irrespective of density.