In the textile industry, that sagging, stretching and loss of form is known as “dimensional instability,” and it is a factor all quality manufacturers consider when producing a textile-based product like clothing or linens, and even raw fabrics.
Through industry-driven standards developed under organizations like the American Association of Textile Chemists and Coloration (AATCC) and the International Standards Organization (ISO), specific dimensional stability tests have been created to assess how garments and fabrics behave under conditions fine-tuned to emulate typical consumer practices. A thoroughly tested fabric or garment must endure such processes as:
Skew/twist/torque tests — these rigorous measures are meant to determine fabric “spirality”, or de-twisting, after machine washes.
Shrinkage/crinkling — ISO test methods specify the use of a square sample of the fabric to determine shrinkage or disfigurement after washing machine use, for both “warp” knit (the fibers held stationary against the loom); and “weft” knit (drawn over and under the “warp” fibers).
Stretch and recovery — this test can determine if a fabric or garment has good “recovery properties” by first marking out both ends of a distance established by the two sides of a fabric sample in its relaxed state, then held at a specified extension for a prescribed period of time, and finally measured again at its relaxed state to determine the percentage of the resulting expansion.
When you want to measure up to these standards, it is important to use a testing service that can:
You need to understand all applicable national and international testing standards.
You need to incorporate the best testing methods into your production plans before manufacturing starts.
Ensure all QC samples are taken directly from the production line, representing your actual product, and not some “ideal” sample that the factory manager would like you to test.
