How can garment manufacturers test for fabric colour bleeding before cutting whole production lots?
Short answer
Perform a quick hot-water immersion test or chemical soap crock test on a 10x10 cm fabric swatch. Agitate the swatch in warm water with mild detergent for 10 minutes against a white cotton cloth to check for dye transfer.
Color bleeding ruins entire garment batches. Before sending bulk rolls to stitching units in Ahmedabad or Surat, always perform a lab soak test:
Hot Water Test: Soak the swatch in 40°C soapy water for 15 minutes. If the water changes color intensely or stains the adjacent white cloth, reject the dye lot or mandate chemical fixative washing (soaping) at a local process house.
