Hollow Yarn

Definition and Overview

Hollow yarn is yarn with a continuous or discontinuous hollow inside the cross section of the fibers that make up the yarn. The hollow structure refers to the shape of the fiber and is not a specific material name such as polyester, nor a fabric or knitting structure name, nor a finishing process name.

The size and number of hollows in the cross section, as well as the outer shape of the fiber, vary by product. Because the hollow part contains air, it is easier to achieve lighter weight than with solid yarn of the same thickness, and it is used in woven fabrics or knits as warp, weft, or both, depending on the application.

Features

Its characteristic is that the hollows make it easy to lower the apparent specific gravity of the yarn and create a bulky, light texture. It is also sometimes used in textiles intended to provide warmth because of the air layer contained inside.

Appearance and hand feel vary greatly depending on light reflection, cross-sectional shape, yarn thickness, and whether it is brushed. Because hollow yarn is not always soft, warm, or highly absorbent and quick-drying, check the fabric weight, density, structure, blend ratio, and finishing together.

• Easy to take advantage of its light weight
• Easier to design warmth through the air layer
• Easy to express a bulky, full texture
• Depending on the cross-sectional design, the appearance of sheerness and luster may change

Main Applications

It is used for outerwear, blousons, pants, sportswear, outdoor wear, and other items that require both light weight and warmth. It is used not only for outer fabrics but also for linings, mid layers, and brushed materials, and is mainly planned for autumn and winter products.

On the other hand, hollow yarn does not by itself determine whether something is for summer or winter. When combined with designs that provide breathability in a thin fabric or with moisture-absorbing quick-drying finishing, it may also be used for lightweight spring and summer clothing.

How to Choose and Handling Precautions

When selecting it, check not only light weight but also fabric weight, thickness, warmth, breathability, strength, pilling, and sheerness in the actual textile. Even with the same hollow yarn, differences in hollow ratio, material, and yarn usage will change handling during sewing and the durability of the product.

Shrinkage and dimensional change from washing are influenced not by the hollow structure itself but by the main fiber material, knit or woven structure, and dyeing and finishing conditions. Before mass production, conduct washing tests and manage according to the care label. High-temperature drying and ironing may cause deformation or changes in hand feel in textiles made with synthetic fibers.

During sewing, bulky textiles and brushed textiles tend to have thicker seam allowances, so match the needle, thread, and feed settings to the textile. To prevent visible needle holes, seam puckering, and seam shrinkage, it is important to carry out sewing tests and check the appearance after washing before full production.

Differences from Similar Terms

Hollow yarn is a term that describes the internal structure of yarn. Irregular cross-section yarn refers to yarn with a cross section other than round, and being hollow is not required. However, there are also yarns that combine an outer shape and a hollow structure.

false-twist textured yarn is a processed yarn that adds crimp through heat and twisting to create stretch and bulk. Hollow yarn may also feel bulky, but the main reason is the internal hollow, and it differs from false-twist textured yarn in terms of structure and manufacturing method.

Frequently Asked Questions