Glossary

• Memory Foam

  Memory Foam was invented by NASA in 1966. The idea was to improve the safety of aircraft cushions, but it was not long before th material was developed further and used in more and more products. Memory Foam is an open cell construction, which reacts to body heat and weight. The more heat applied, the softer the material gets. This, in turn, allows the weight applied to sink deeper. Memory Foam can be made at various densities to result in different tensions/firmnesses.

  The crucial element of Memory Foam is that it softens and moulds to the body shape. This ability allows for very accurate contour support and weight distribution. This ability makes Memory Foam a desirable material for mattresses. Some mattresses are completely Memory Foam, perhaps using different layers of various densities. Some mattresses use Memory Foam to compliment a Spring Unit.

  As Memory Foam requires heat to achieve its desired state, the heat is stored. Some people are not keen on Memory Foam as this heat can gradually build, resulting in a warm bed. However, this stereotype can be seen as outdated, as many manufacturers have solved the issue by applying new techniques to compliment the Foam. Techniques such as Outlast and Coolmax. Memory Foam is also Hypoallergenic and is therefore very popular with Asthma and Allergy sufferers.

• Open Coil

  An Open Coil spring unit is made from a continuous piece of wire. This wire can be made from various different gauges of wire, ending in differing firmnesses. The idea behind an Open Coil spring unit, or Continuous Springs as they are sometimes known, is that the spring unit can be made quickly, efficiently and therefore for little cost. Open Coil spring units tend to be the reserve of the entry level models on the market. However, some manufacturers have perfected the technique and the end result is extremely successful.
  
  A single piece of wire will be placed in a machine, bent into coils. Each coil will be joined at the top, the bottom or both and the result is a spring unit made of one wire. The reason this works well, is that the springs can support one another and share any weight or pressure across the surface. Other methods of spring units include Twin Sprung or Pocket Sprung.

• Quilted / Micro Quilted

  Quilting is the stitching technique used to join or attach the mattress' surface layers of fibres to the surface material (the ticking). There are various different techniques which can be used to join these layers, but Quilting is common. Traditionally, Quilting offers a softer surface feel than Tufting as the layers are not held together so tightly. Also see Diamond Stitching or Micro Quilting for variations on Quilting.