So What’s the Deal With Rayon?
The word “Rayon” was first coined as a generic term for “regenerated cellulose fiber,” which refers to the manufacturing process used to create it. Rayon is known the world over as the first man-made textile and was invented and perfected in the late 1880s-1890s. The first chemist to accidentally stumble upon the beginning stages of manufacturing such a fiber was a British man named, Sir Joseph Wilson Swan (1). I mentioned in my last mattress article that cotton cellulose is sometimes used in the production of explosives, but in 1884 and 1885, cotton cellulose, which was dyed and treated with nitric acid, was just as likely to explode the gun in which it was loaded as it was the bullet it was meant to project (1,5). So, Sir Joseph Wilson Swan decided to experiment. His finished product were fibres made of nitrocellulose that had been chemically treated and changed back to nonflammable cellulose. However, these experiments were soon after abandoned. It wasn’t until an industrial French chemist by the name of Hilaire Bernigaud, comte de Chardonnet, entered the scene that cellulose regeneration was revisited and perfected. After the commercialization of “Chardonnet silk,” in 1891, everyone wanted to get in on this synthetic fabric action (1).
There were several key players from both France and Britain in the textile game during this time period. From their efforts, three successful methods were discovered for cellulose regeneration. The manufacturing process most commonly used today was discovered in 1891 by a group of three British scientists, Charles F. Cross, Edward J. Bevan, and Clayton Beadle (1). By 1901, this new fiber was being mass produced under the name “viscose rayon.” The second form of rayon we will look at is High Wet Modulus Rayon or HWM Rayon, which is more commonly known as Modal or Lyocell ™ (2). Both forms of Rayon are commonly used in mattress fabrics as well as many sheets, pillows, and other sleep essentials, so we will take a look at them both.
Both viscose rayon and HWM Rayon are favored materials due to their being relatively inexpensive to make. They are also remarkably soft to the touch, are about 50 times more absorbent than their rival fabric, cotton, and have a very pleasing fluidity to the way they move. Rayon’s ability for moisture retention makes it an ideal summer fabric since it helps with lowering temperature (no form of rayon that I’ve stumbled upon yet is known for being proficient at heating, just cooling) however, once viscose rayon becomes fully saturated, it’s overall fiber strength drops by about 75% making it more susceptible to damage as well as shrinkage or permanent stretching. Therefore, submersion or full saturation should be avoided and dry cleaning sought as an alternative. Modal is more resilient in the face of saturation and is generally machine washable. Modal is also commonly blended with other materials such as polyester, spandex, or cotton to add strength or to give it a silkier hand (2). Rayon is easily damaged and discolored by microorganisms, such as bacteria and mildew, as well as heavy direct sunlight and heat, such as that from an iron. These stressors can cause the fibers to grow weaker, loose or distort their color, and eventually begin to yellow, therefore a mattress or pillow protector is mandatory for any products made from a high percentage of rayon (3).
While all forms of Rayon are derived from either wood pulp or plant cellulose, such as that from cotton seeds, it is not a natural material and should not be mistaken as such. The manufacturing of this product requires the use of many caustic chemicals and releases many pollutants into the environment. Most customers won’t know this, but those that are well versed on the “evil’s of corporate manufacturing,” as one of my customers put it, will call you on your bluff if you suggest that Rayon or Modal are “natural.” Try suggesting instead that they are made “using natural wood and plant fibers,” or, “from natural materials.” For those more nature-savvy customers, this line generally draws an eye roll but little more, and those less-versed won’t spot the difference.
In sum, Rayon holds the exciting title of being the world’s first man-made fiber. Rayon is praised for its ability to cool the body, for it’s silk-like hand, for being fairly inexpensive to manufacture, and for being twice as absorbent as cotton. Rayon should never be fully saturated and loses a terrifying 75% of its tensile strength when wet, it’s highly susceptible to discoloration and break down when exposed to microorganisms and heavy, direct light or heat, and should therefore always be paired with a mattress protector when used as the surface layer in a mattress or a pillow. Rayon is an ideal and affordable choice for a quality sleep surface as long as it’s not neglected.