Raw Silk

Definition and Overview

Raw silk is a silk filament yarn made by boiling cocoons to loosen the fibers and reeling together multiple cocoon filaments. Because the sericin coating on the surface of the cocoon filament is left intact, it differs in hand, luster, and behavior when dyed from silk yarn that has been scoured to remove the sericin.

As a material name for textiles, it generally refers to silk. In the synthetic fiber field, however, the term is also used for stretched or unprocessed filament yarn. In material labels and specifications, it is necessary to confirm whether it refers to silk raw silk so there is no confusion.

Texture and Function

Fabrics made with raw silk are characterized by a slightly crisp hand from the sericin, natural firmness and body, and an understated luster. Depending on the conditions of scouring, dyeing, and finishing, suppleness, slickness, and the appearance of luster can change significantly.

Because silk has moisture absorption and release properties, it is a material that helps regulate humidity inside clothing. However, breathability, warmth, and drape vary depending on the weave structure, density, yarn thickness, and blend ratio, so product performance cannot be judged by the name raw silk alone.

Main Uses and Suitable Items

Raw silk is used as warp or weft in woven fabrics and is used for blouses, dresses, skirts, formal dresses, Japanese clothing applications, and other items that make use of its delicate appearance and moderate firmness. From lightweight to medium-weight fabrics, a wide range of expressions is possible by changing the weave structure and density.

It is often used in spring and summer apparel that takes advantage of its moisture absorption and skin feel, but it is also used for year-round dresses and formal applications intended for layering. When deciding on applications, consider not only the season but also sheerness, required strength, and whether lining is needed.

• The surface feel changes depending on the degree of scouring and the dyeing method.
• When making use of firmness, also check compatibility with interlining and lining.
• For light colors and lightweight fabrics, confirm sheerness and the visibility of seam allowances in advance.

How to Choose and Handling Precautions

When selecting, confirm whether it is raw silk or scoured silk yarn, as well as the weave structure, fabric weight, density, blend ratio, and finishing treatment. Before mass production, evaluate shrinkage, color transfer, and changes in texture caused by washing or dry cleaning, using the actual fabric together with accessories.

Because water washing may cause shrinkage or changes in texture, it is basic to follow the care label for each product. Strong friction and prolonged sunlight can cause pilling, whitening, and fading. During storage, avoid humidity and direct sunlight.

Before cutting, unroll the fabric and make it settle, and check the grainline. With lightweight or slippery fabrics, shifting during cutting, puckering during sewing, and visible needle holes may occur. It is important to adjust the conditions for needle, thread, and stitches through test sewing.

Differences from Similar Terms

Silk is a broad term that refers to silk fibers and silk products in general made from silkworm cocoons and similar sources. Raw silk refers to the filament yarn reeled from cocoons with the sericin left intact. Therefore, not all silk materials are raw silk.

Silk spun yarn is a spun yarn made by spinning short silk fibers, and its production method and appearance differ from raw silk, which uses long fibers continuously. In addition, since the term raw silk may be used broadly as a sales name for fabric or yarn, confirm in the material specifications whether it is synonymous with cocoon-derived raw silk.

Frequently Asked Questions