Heat Setting
Heat setting is a finishing process that mainly treats thermoplastic fibers with heat and tension to stabilize dimensions and shape, and to set wrinkles, pleats, and width.
Contents5 sections
Definition and Overview
Heat setting is a finishing process that uses the property of thermoplastic fibers, which change shape when heat is applied and are likely to retain that state after cooling. It adjusts fabric to a specified width and length, and stabilizes its dimensions and shape through heat treatment.
It is mainly applied to woven fabrics and knits containing polyester and nylon. It may also be incorporated as a process before or after dyeing and functional finishing, and it is important to note that the process name does not indicate the material name or weave structure.
Features
It makes it easier to adjust the fabric width, length, and stretch condition, helping to suppress dimensional changes during subsequent processes and product use. It is also used to fix the appearance of heat-formed pleats, texture, and three-dimensional effects.
The hand of the fabric after heat setting varies depending on the fiber type, fabric structure, temperature, tension, and aftertreatment. While it may add firmness and smoothness, excessive heat or tension can lead to stiffness, gloss, or reduced stretch.
Main Applications
It is used for polyester and nylon apparel fabrics that require dimensional stability and shape retention. Its applications are broad, including shirts, blouses, pants, skirts, dresses, jackets, sportswear, uniforms, and outerwear.
It is also a related process for skirts and dresses that make use of pleated appearance, knits where stretch needs to be controlled, and synthetic taffeta and tricot. It is not limited to a specific season, and is selected according to the fabric material, design, and required appearance.
Selection and Handling Notes
When selecting a fabric, check not only whether it has been heat set, but also the blend ratio, finished width, fabric weight, shrinkage rate, stretch, and dimensional change after washing. If the goal is pleats or shape retention, it is reassuring to also perform a washing test on the finished product.
When ironing or pressing during sewing, control the temperature and time according to the fabric's heat resistance. In particular, thermoplastic fibers may become glossy, shrink, deform, or show fading at high temperatures, so it is necessary to use a pressing cloth and test on scrap fabric in advance.
Heat setting overlaps in purpose with shrinkproofing and shape-retention finishing, but they are not the same. Shrinkproofing mainly suppresses shrinkage from washing and similar causes, and shape-retention finishing mainly aims to maintain wrinkles and appearance, whereas heat setting refers to fixing dimensions and shape through heat.
- For blended fabrics, check the heat resistance and shrinkage difference of each fiber.
- Before cutting, unwind the roll and let the curl and tension settle.
- Before mass production, check the appearance and dimensions after pressing, washing, and drying.
Frequently Asked Questions
Does heat setting prevent shrinkage in washing?
It may help reduce dimensional change from washing, but it is not a process that completely eliminates shrinkage. It varies depending on the fiber type, blend ratio, knit or weave structure, sewing conditions, and washing method. Judge by the fabric specification shrinkage rate and the results of the product washing test.
Can heat-set fabric be ironed?
If you follow the care label and the fabric's heat resistance, ironing is possible. However, thermoplastic fibers may develop gloss or deformation at high temperatures. Set the temperature low, use a pressing cloth, and check an inconspicuous area before pressing.
