Casual and formal clothing made with 100% cotton have many advantages. It can be worn year round and is soft and comfortable. It retains body heat in cold weather and absorb perspiration in hot and humid climates. It is hypoallergenic and is the fabric of choice for those with sensitive skin.
Even though clothes made of cotton wrinkles and shrinks, they are easy to care for and are machine washable. Designer children’s clothing as well as designer cotton clothing for men and women that have particular finishes, trims and dyes, can be dry cleaned. The fabric is strong, durable and is easy to darn. It softly drapes the body without clinging, and can be printed on and dyed in a panoply of colors. These qualities have made cotton the most widely used fabric for clothing in the world. What could be better?
When cotton yarn or fabric is mercerized, some of the above qualities are greatly enhanced. Clothing made with this cotton has a softer feel and is more lustrous than the conventional kind. As a result of the treatment, it has a greater moisture sorption capacity and is more comfortable to wear in hot, humid climes than conventional cotton. This capacity also allows the treated fibers to take up and retain dyes better and to exhibit richer and more brilliant colors and prints. Clothing made with mercercized fabric is stronger and more durable, and less likely to shrink or lose shape or color after multiple washings.
The treatment process usually demands the use of better quality, long staple cotton such as Egyptian, Sea Island, or Pima greige goods to achieve the best results. The latter is one reason why this is a favorite fabric used to make designer children’s clothes as well as for stylish, upscale clothes for men and women. Both the mercerization process and the quality greige goods employed makes for a much improved product and a better clothing buy and value than clothing made with conventional cotton.
What Does Mercerization Do to Cotton Fiber?
Mercerized cotton is made by briefly immersing pretreated (singed, scoured, bleached, etc.) cotton yarns or cotton fabric in a strong solution of sodium hydroxide under tension and then washing the yarn or fabric clean. This chemical treatment modifies and improves the physiochemical surface and internal structure of cotton fibers.
Mercerization under tension causes cotton fibers to swell irreversibly. This swelling causes the flat and twisted kidney bean-shaped fibers to uncoil and to become permanently cylindrical, straight and nearly circular like a tube. Cotton fiber cross sections can increase by as much as 50%. As the cell walls swell, the exposed surface of the cell wall and the size of pores in the cell wall increase significantly. In addition, the fibrous secondary cell walls and cell contents become more solid, gelatinous and translucent. These physical changes are directly related to the increase in cotton fiber luster, strength, durability, and affinity for moisture and dyes.
Unlike the flat, twisted shape of the conventional cotton fibers, the smooth, rounded cylindrical shape of the swollen cotton fibers (made under tension) are similar to thousands of polished surfaces that receive and reflect light. And with a new gelatinous, translucent interior that prevents absorption of light, the smooth round reflective cotton fibers come to have a lustrous sheen.
When the fibers swell and uncoil during the mercerization process, the formerly twisted fibers become relaxed and smooth. Simultaneously with the swelling, the cell material within the fibers becomes more tightly compacted together. This change strengthens the cotton fiber making it better able to withstand stretching and breaking and makes it more durable and able to keep its shape.
The mercerizing process alters the fiber so that it adsorbs more water on its expanded crystalline cell wall surface and absorbs more water into the spaces within fiber through enlarged pores. With this modification, mercerized fiber absorbs more perspiration and improves wearing comfort. Also, dyes are more easily taken up
making color penetration more lasting and pronounced than in conventional cotton.
Thanks to John Mercer’s discovery of the basic process more than a century and half ago, we can enjoy this luxurious fabric today that makes cotton clothes more comfortable to wear, better looking, longer lasting, of higher quality and easier to care for than regular cotton garments. Though usually more expensive than ordinary cotton garments, it is a better buy for smart shoppers.