A Visco Elastic Foam Mattress – Easier to Lie on than it is to Say!
To help take some of the confusion out of buying a new mattress, Cheap Mattress Reviews was founded to provide you with consumer reviews of all the leading mattresses available today.
When you are searching for a new mattress in store or online you may come across the term “visco elastic foam” and wonder exactly what it is – it is a bit of a “mouthful” to say, after all. Well, we’re happy to report that a visco elastic foam mattress is much easier to lie on than it is to say!
Basically visco elastic foam is another name for “memory foam” – the material that around twenty years ago started to become available for use in mattresses and specialist pillows worldwide and which has gradually risen in popularity since.
Visco elastic foam started life being developed as “low spring back foam” or “temper foam” by NASA in the 1960′s, as a way to cushion the extreme forces experienced by their astronauts during take off. It was effective in providing great elasticity and comfort as it molded to the body shape and temperature.
When the foam was released to the public domain it was first used in medical and sports equipment (like lining for helmets or as foam for beds where patients had to be immobilized for a long period of time.)It was some Scandinavian scientists and entrepreneurs that began developing and testing the foam for use in bedding in the early 1990′s and, following many years of research, the high-quality Tempur-pedic Swedish Mattress was introduced to the US market around that time. They opened manufacturing plants in the US and for the last 20 years have been the benchmark by which visco elastic foam mattresses or “memory foam” mattresses are judged.
There have been many copies of the Tempur material. Even Tempur-pedic themselves have added a HD or “High Definition” foam that improves on the initial foam.
Initially the visco elastic mattress from Tempur-pedic was too expensive for widespread consumption. Over time the production methods have been adjusted and the mattresses have come down in price, but if you are considering one of these items you should be aware of the vast differences between a high-quality memory foam and a lesser grade one.
Also read the labels carefully as the quantity of memory foam used will vary and may well be mixed with larger quantities of other foams. Anything less than 2 inches of memory foam will serve little purpose, whereas too much will make it too soft. Most of the best manufacturers control the amount of foam used carefully and this will help to explain the large price differences between different brands of memory foam mattresses.
Technically, the foam will usually be polyurethane-based, with other chemicals used to increase its viscosity and density. The density of visco elastic foam is important, as the higher the density the better it will mold to the body heat by softening up and enveloping the sleeper, giving it its body-hugging qualities that it has come to be known for. A lower-density foam will usually be more responsive to pressure but less responsive to heat. Either way a visco elastic mattress will usually be highly supportive, but heavier than a conventional inner-spring mattress.
The comfort of the mattress is usually measured in IDF (Indentation Force Deflection), which is the force required to make a 1 inch dent in a foam sample. This rating will usually be between 10 and 16, with 10 being super-soft and 16 being firm. Some people dispute that this is a useful reading as to the comfort of memory foam mattresses though, and that density is a better measurement of the comfort it will provide. High quality memory foam generally has a reading of 5 pounds per cubic foot or above. Those you will find on the market will start at a reading of 1 and you will find many in the 3 – 4.5 bracket and notably few at 5 or above.
Another variable with visco elastic foam is the cell structure. If the foam has a tight cell structure the mattress will be less “breathable” as air flow will be restricted. Those with a more open cell structure will be more breathable.