Foam
Polyurethane Foam
Traditionally, foam in upholstered furniture (such as couches) is a polyurethane-based foam, which is 2/3 Polyurethane ingredient and 1/3 Isocyanate ingredient. Polyurethane foam is very flammable, and requires toxic flame retardants by law. In addition, isocyanates have a harmful impact on health, including, irritation of skin and nose, difficulty breathing, and chest tightness. Isocyanates include compounds that are classified as potential human carcinogens, and are known to cause cancer in animals. Hazardous exposures (as may happen in the factory) may result in asthma and lung problems, as well as irritation of the eyes, nose, throat and skin. Polyurethane foam is very durable and will last a very long time in a landfill, as it is not biodegradable.
Soy Foam
The current market is in a craze over soy-foam. Marketed as being better for the environment than polyurethane based foams, we did some research to see what this 'green' foam was all about. As it turns out, Soy foam is not much better than poly-based foam, and some people would argue that it has the same impact. Soy foam is actually made the same way as the polyurethane based foam, with 20% of the mixture being replaced as soy product. So the foam is 20% soy, 33% isocyanates, and 47% polyurethane. Due to the polyurethane content, the foam still requires the toxic flame retardants, and the foam contains the same level of isocyanates. Currently, soy foam also biodegrades at the same rate as poly-based foam. The reason for the low percentage of soy content is that when soy is present at higher levels it produces an undesirable, burnt smell. In addition, the use of pesticides and fertilizers on the soy crop have a negative impact on the environment, as do the mono cultures in which soy is planted. Soy is such a diverse and valuable food source that it may not be used best as a plastic substitute.
Natural Latex Foam
Latex is made from the sap of the rubber tree. It is made up of about 95% natural rubber, and 5% vulcanization and curing factors, which are usually washed out during the final stages of manufacture, resulting in a product that is 99% natural rubber. Natural Latex is anti-micorbial, naturally hypoallergenic and resistant to dust mites, mold, and mildew. Natural Latex is also biodegradable. There are two processes for creating a natural latex foam, the dunlop method and the talalay method.
- Dunlop: The latex is whipped with air to become foam, then heated, vulcanized and cured. This is the least expensive way to produce latex matresses, but the matress may become brittle over time, reducing the products life.
- Talalay: The talalay method is much more complicated than the dunlop method. The raw latex is mixed with soaps and curing agents, then cooled. The latex is then whipped with air until it becomes a soft foam, and poured into a mold with iron rungs (to form the shape of the mattress). A vaccuum removes air bubbles and distributes the liquid rubber evenly through the mold. The latex is then frozen and heated to 220 degrees Celcius to remove air, provide even firmness, and prevent particles from settling at the bottom. The latex is then removed from the mold and washed 5 times with fresh water in order to remove residual soaps, natural proteins, and curing agents. The foam is then dried and tested. The Talalay method has increased durability and support, and will not get brittle over time.
Synthetic Latex Foam
Synthetic Latex, also known as styrene-butadiene rubber (SBR), is derived from petroleum, which increases the flammability of the latex. Mattresses made with SBR require flame retardants that can be harmful to human health, and release toxic chemicals when burned.