Latex Overview
Although they have been available for many decades, latex mattresses are currently experiencing a resurgence in popularity, particularly in Europe. In general, latex shares many of the benefits of memory foam, particularly in terms of its exceptional support and durability. However, latex lacks the highly conforming nature and slow recovery time that characterize memory foam. For those who dislike these aspects of memory foam, whether due to the warmth of the mattress, difficulty in changing positions or otherwise, latex is a very compelling alternative. Fans of latex praise its well-balanced support, long lifespan (which in some cases can exceed 20 years) and allergen resistance. Critics cite challenges in finding the perfect combination of comfort and support, as well as the somewhat rubbery smell of latex mattresses.
Latex Mattress Construction
Like memory foam beds, latex beds tend to be relatively simple in their construction. Typically, a latex mattress consists of anywhere from 1 to 4 layers, with the bottom layer (known as the “core”) being the firmest, and each layer above getting progressively softer. The core, which provides the underlying support for the mattress, tends to be about 5-6″ thick and is typically made from either relatively dense latex (in high-quality latex mattresses) or polyurethane foam. The upper layers, also known as the “comfort” layers, are designed to give the bed a softer feel and are most often made from either softer latex or memory foam.
Latex typically contains numerous “pincore holes” — deep, cylindrical holes spread throughout the mattress to help soften its feel. Larger pincore holes create a softer feel. Some manufacturers place different-sized holes in different parts of the mattress in order to offer different zones of support and comfort for the various parts of the body.
Types of Latex
Latex mattresses can be made from either natural or synthetic latex, or (more typically) a blend thereof. Though all-natural latex mattresses are available, they are the least common and most expensive. Natural latex, produced from the rubber tree, is known for its softness and elasticity, as well as its biodegradability and inherent resistance to bacteria, mold and dust mites. That said, as a natural product, it is inherently subject to greater variations in quality. Synthetic latex, made through a chemical process using petroleum-based materials, shares many of the same physical properties as natural latex, but often has a slightly stiffer feel and is thought by some to better maintain its resiliency over a very long period of time. Blends of natural and synthetic latex generally aim to capture the advantages of both natural and synthetic latex and thus have become quite popular. Mattress manufacturers using blended latex often claim that it combines the elasticity of natural latex with the consistent quality and durability of synthetic latex.
Some latex also includes “fillers,” tiny particles of clay or other materials that are mixed into the foam, making the resulting latex less costly, but also stiffer and less durable. The term “pure latex” typically refers to latex that does not include fillers, and can be applied to either synthetic or natural latex. Most higher-quality latex mattresses use pure latex.
Latex Production Techniques
There are two different production processes used to make latex mattresses, the differences in which are largely a matter of personal preference. The older, more established process (dating back over 75 years) is known as Dunlop, while the newer, more involved (and more expensive) process is known as Talalay. In the Dunlop process, liquid latex is “whipped” with air until it becomes wet foam, at which time it is poured into a mold, hardened, and vulcanized. In the Talalay process, the wet latex foam is similarly poured into a mold, but extra room is left at the top of the mold. Once the mold is sealed, air is vacuumed out of the mold, causing the foam to expand such that it fills the empty space inside the mold. The mold is then frozen and quickly vulcanized, locking in the expanded structure of the foam. Not surprisingly, Talalay latex is generally softer and less dense, while Dunlop latex tends to be firmer and heavier.
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