Thermal Gradient
Polymeric dye dispersion inside polyester filaments turns mobile under heat transfer conditions. Sublimation migration describes the lateral displacement of vaporized disperse colorants during high temperature setting stages. Fabric printers encounter this gaseous transfer defect when thermal presses exceed safe operational thresholds.
Contamination spreads onto adjacent white grounds during the fixation stage.
Vapor Pressure
Disperse dyes change from solid particles directly into gas phases without passing through liquid states. Temperature increases accelerate molecular kinetic energy until gas pressure overcomes fiber matrix constraints. Volatile colorant molecules drift outward through microscopic interstices within synthetic yarns.
Processing speeds dictate the duration of thermal exposure inside stenter frames.
Boundary Layer
Air velocity variations across the fabric surface create uneven vapor condensation zones. Exhaust hoods capture escaped gas before redeposition ruins adjacent material yards. Mill technicians monitor temperature sensors to prevent the uncontrolled gaseous drift phenomenon.
Edge zones cool faster than center webs, creating distinct concentration gradients across the roll width.
Color Fastness
Post-production washing removes loose surface residues left by thermal redeposition. Standard laboratory tests evaluate staining severity on adjacent multi-fiber test ribbons. Batch rejections occur when color transfer exceeds established grey scale tolerance ratings.
Finished garments retain color integrity only when production ovens maintain strict thermal uniformity.
