The production process of silk fabrics

Sorting and softening the cocoons

A silk mill is a factory where cocoons are processed into silk thread. In the silk factory, cocoons are sorted by various characteristics, including color and size, so that the quality of the finished product is uniform. The cocoons must then be soaked in hot water to loosen the silk proteins. Although silk has approximately 20% silk gum, only 1% is removed at this stage. This way, the gum facilitates the next stage of silk binding to form silk threads.

Reeling the Filament

Reeling can be done manually or automatically. The cocoon is brushed to find the end of the fiber. It is threaded into a porcelain eyelet and the fibers are then reeled onto a wheel. Meanwhile, diligent operators check the fibers for defects as they are reeled.

As each filament is almost finished winding, a new fiber is twisted onto it, resulting in a long, continuous thread. The serine helps the adhesion between the fibers.

Packaging the Skeins

The end product, the raw silk filaments, are reeled into skeins. These skeins are packaged into bundles weighing 5-10 pounds (2-4 kg), called books. The books are further packaged into bales of 133 pounds (60 kg) and transported to manufacturing centers.

Forming Silk Thread

Silk threads, also called yarn, are formed by throwing, or twisting, rolled-up silk. First, the raw silk threads are sorted by color, size and quantity. Then, they are soaked in warm water mixed with oil or other substances to soften the silk gum. Soap is used to soften the silk glue. The threads are then dried in the sun.

When the silk threads are wound onto a bobbin, they are twisted in a special way to obtain a thread of a certain texture. For example, "monofilament" consists of several silk threads that are twisted together in one direction. They are twisted tightly together for sheer fabrics and loosely for thicker fabrics. Combinations of monofilaments and untwisted fibers can be twisted together in a certain pattern to obtain a desired fabric texture, such as crepe, gauze or tapestry. The fibers can also be manufactured in different patterns for the terry of the fabric, or for the exterior of the fabric, or for the interior of the fabric.

The thread is passed through a roller for a more uniform width. The yarns are inspected, weighed and packaged

Finishing of Silk Fabrics

After degumming, the silk thread is milky white. Next, it can be dyed as yarn or after the yarn has been woven into a fabric. The silk industry makes a distinction between pure dyed silk and so-called weighted silk. In the pure dyeing process, silk is colored with dyes and may be treated with water-soluble substances such as starch, glue, sugar or gelatin. In order to produce weighted silk, metallic substances are added to the fabric during the dyeing process. This is done to increase the weight lost during the degumming process and to increase the weight of the fabric. If weighting is not done properly, it can reduce the life of the fabric, therefore, pure dyed silk is considered to be the superior product. After dyeing, silk fabrics can be processed by other processes such as bleaching, embossing, steaming or stiffening.