H R Foam- HR Foam or High Resiliency foam is a special kind of foam used in mattresses Unlike PU or other kinds of foam, it has more resiliency, meaning the ability to bounce back up.
High resilience is a polyurethane foam that has a much higher responsiveness than memory foam, which has a slower response. Because of this, those that enjoy more of a bounce in their mattress will gravitate towards this type of foam.
High resilience foams are much less popular than memory foam, but they make up important layers of many popular mattresses. Oftentimes the transitional layer or base layer of memory foam mattresses will contain high resilience foam at high densities. This provides a more even feel across the mattress, and less of a sinking feeling that memory foam alone would have.
Like all polyurethane foam, high resilience foam is made of a blend of polyurethane and has a tendency to off-gas. If you are susceptible to lung issues, please do additional research on the quality of foams before purchasing.