Cellular material existing in different densities (25 kg/m3 to 60 kg/m3) polyurethane foam material is airy, light, easy to handle and has a strong power elasticity and firmness different offers.
Starting at 35 kg/m3, these foams are called foam "High Resilience" (HR), their elasticity and comfort are superior.
Polyurethane foam can be manufactured according to the technique of continuous cutting or molding individual.
• 20 kg / m³ to 25 kg / m³: polyether foam
• 25 kg / m³ to 35 kg / m³: polyurethane foam
• 35 kg / m³ to 60 kg / m³: Polyurethane Foam High Resilience (HR)
Today the polyether / polyurethane foam (below 35 kg / m³) is really the entry level, the price is very affordable for small budgets and lightweight, but life is short. Avoid if possible and not to be confused with RH.
mattresses in High resilience polyurethane foam (HR) are the most common. The principle of zoning cells can vary according to the resilience support areas (soft for the feet and head, close to the pool) to keep the body perfectly horizontal.
should focus on density (minimum 35kg/m3) and focus your choice on the thickness of the foam core mattress (minimum 14 cm) height one rather than "visual", all molded HR if possible.
It is very good value for money without going to the "lowest bidder". Bultex always offers mattresses HR polyurethane foam of 38 kg/m3. Dunlopillo mattress offers HR polyurethane foam 40 kg/m3. HR are the cheapest, but firmer, and therefore they are often more misleading is the archetypal product firm / very firm welcome tonic. Suitable for young sportsmen and less fortunate. It is often the first purchase.
Do not link density firmness of mattress : there are also foam mattress "cheap" in 25 kg/m3 density firmer than the 38 kg/m3 as to increase firmness, some manufacturers add the polyol (component organic chemical) and yet the mattress will sag faster than the density of 38 kg/m3 for resilience (elasticity) or density of the mattress is low.
Caution : for moisture, air circulation is essential (no board installed under the mattress or bedding placed on the floor).
Source:
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