Mattresses: Latex versus Memory Foam

When people shop for a mattress they often believe that latex foam and memory foam are the same substance. But they're not. They are two separate substances which provide for completely different sleeping experiences altogether. They also both have their pros and cons which need to be considered before making a purchase. In order to help you better understand before you buy a mattress, we’ll look at both types of foam and what they offer.

The Basics of the Latex Foam

Latex foam mattresses generally fall into one of two categories: natural or synthetic. Synthetic latex is a completely man-made substance which was developed during World War II when there was a shortage of natural latex. It is seldom used in bedding these days because it is petroleum-based and is prone to letting off harmful chemicals as it deteriorates. For the most part, latex foam mattresses will be classified as natural latex rubber.

That said, even natural latex mattresses are usually not 100% pure. Although it's possible to buy mattresses of that type, pure latex rubber is very expensive making it prohibitive for a bed mattress most people can afford. Therefore, most latex foam mattresses use a combination of natural latex rubber and some synthetic materials. The synthetics are considered to be completely safe and do not let off any toxic chemicals.

How Latex Foam Mattresses Are Made

Latex foam comes from the sap of rubber trees. To make a mattress the sap is extracted from the rubber tree, treated, and then mixed with the synthetic additives to form a soup-like "batter." From there the manufacturer can choose either the Dunlop process or the Talalay process to construct a mattress. The Dunlop process is far away the more commonly used because it has a lower cost of production and provides a more firm and sturdy foam.

With the Dunlop process the batter is poured into a mold and baked at low temperature for a considerable amount of time. As it bakes, impurities drift to the bottom where they collect in the floor of the mold. For this reason, the bottom half of a mattress created with the Dunlop process tends to be a bit more firm than the top of the mattress. When the baking is complete the mattress is allowed to cool before it's removed from the mold.

The Talalay process is a bit more complicated and expensive to do. It begins by pouring the same batter into a mold with a slightly different construction over a Dunlop mold. The mold is sealed off completely and then all air removed with a vacuum. By removing the air, manufactures end up with a more consistent product rather than having one surface being more firm than the other. With the air removed the mold is then frozen very quickly, in a process called "flash freezing", in order to stabilize the liquid and make it solid. Once the mold again reaches room temperature it is opened and the mattress removed.

Differences between the Two

The primary difference between the two latex foam methods is one of firmness. The Dunlop latex tends to be more firm while Talalay latex is softer. Talalay is obviously more expensive, so it is reserved for higher-end latex foam mattresses. For people who plan to use a mattress topper the difference in the two foams probably will not even be noticeable. Unless you absolutely must purchase a Talalay mattress, you'll probably do fine with a Dunlop one.

The Basics of Memory Foam

Memory foam is a polyurethane product with certain visco-elastic properties that cause it to react much differently to heat and pressure than typical latex foam. It is a space age product originally developed by NASA scientists in the 1960s.

While designing the nation's fleet of space vehicles they needed a material for the seat cushions that could withstand the G-forces of liftoff while still providing appropriate support and comfort for astronauts. They also needed a material that would be sensitive to body heat so that the seat cushions would still be conforming even in space. From their research memory foam was born.

In the 1980s NASA released the formula for memory foam into the public domain. From there several manufacturers began using the formula to produce mattresses and seat cushions. Today there are manufactures all over the world creating memory foam for any number of purposes.

How Memory Foam Mattresses Are Made

A memory foam mattress is made much the same way as a latex mattress using a process similar to the Talalay process. When constructing a memory foam mattress however, that specific process is far less important than the actual process of creating the foam itself. Creating the foam is a complicated process of combining and processing various chemicals according to a specific formula. If done correctly you achieve a material which is very dense, yet porous, which allows air to move through it very easily.

The Better Mattress

It is pointless to argue over which type of mattress is better. Both latex foam and memory foam have their advantages and disadvantages, and ultimately the choice will be left up to the individual consumer. As a general rule it is fair to say that latex foam does not sleep as hot, is hypoallergenic, and is more comfortable for some health conditions like rheumatoid arthritis and spinal fractures. On the other hand, memory foam provides more support and is denser. Memory foam also tends to have a longer life than latex foam.