The goal of our Know Your Fibers series is to provide info about different types of fibers for our readers. This quarter, we take a look at regenerated cotton.
What is regenerated cotton?
Also known as shoddy, regenerated cotton is mechanically re-fiberized virgin cotton that has been spun into yarn. Fabrics woven or kitted from yarns or the yarn itself are the feed source.
How is cotton regenerated?
Yarns, fabrics, or end products are re-fiberized by processing through machines that tear the materials apart. However, these materials are never completely re-fiberized. Even with the maximum degree of mechanical work, pieces of yarn that were not re-fiberized remain. With less work, more yarns and, in some cases, parts of the woven or knitted fabric remain intact. As a result, not all regenerated (shoddy) cottons are the same.
Most regenerated cotton used in nonwoven roll goods production is produced from traditional woven and knitted cotton fabrics. To produce these fabrics, virgin cotton fibers are spun into yarn, and the yarn is woven or knitted into fabric. These fabrics are then scoured and purified to make the fabric white and absorbent.
How are fabrics are used after re-fiberization?
Many times, these fabrics are treated with optical brighteners and finishers to make them whiter and softer. These chemical treatments are not removed by the re-fiberization process and remain on the fibers.
The purified woven or knitted fabrics are made into t-shirts, undergarments, and sheeting fabrics. In addition, the fabric trimmings from producing these end products can be re-fiberized and used to produce white, absorbent, nonwoven roll goods.
Yarns and fabrics that have not been purified (griege fabric) are also re-generated to produce fibers that can be used to manufacture nonwoven fabrics, provided the fabrics do not require absorbency or whiteness.