Thermal Stabilization
Passing fabric through a heated oven while it is held under tension fixes the internal structure of the synthetic fibers. The process of stenter frame heat setting prevents the material from shrinking or creasing during subsequent washing and wearing. It is a critical step for fabrics containing polyester, nylon or elastane.
Crystalline Transition
Heat allows the polymer chains inside the fiber to relax and reform in a more stable arrangement. During stenter frame heat setting, the temperature must be high enough to reach the glass transition point of the plastic but low enough to avoid melting the material. This creates a permanent memory of the flat, wide shape of the fabric.
Tension Management
Grips or pins hold the edges of the cloth to control the finished width and the weight per square meter. Careful adjustment of the stenter frame heat setting ensures that the grain of the fabric remains straight. If the tension is uneven, the fabric will suffer from bowing or skewing that makes garment cutting impossible.
The dwell time inside the oven is synchronized with the speed of the machine to ensure every meter receives the same amount of energy.
Finish Permanence
Chemicals applied before the oven are cured and bonded to the fiber surface during this stage. The result is a dimensionally stable fabric with a consistent hand feel.
