Dye crocking occurs when the dyestuffs break away from the surface of the fabric due to the incomplete penetration of the fibers, yarns, or fabric. When a fabric “crocks” the loss of color is more pronounced in the areas of the garment that are exposed to friction or abrasion during wear (collar, cuffs, pocket edges, underarms, elbows). If a fabric is susceptible to dye crocking, the “high points” of the garment such as the seams, selvage, stitched or double layers of fabric will crock more severely than other portions of the garment.

The crocked areas of the garment are seldom noticeable prior to the dry cleaning, laundering or wet cleaning processes. When the garment is processed, the dry cleaning solvent or water will flush the loosened dyestuffs from the fabric, revealing its true (lusterless or faded) condition. When a fabric is prone to dye crocking, the condition of the garment will worsen each time it is worn. Subsequently, the fading of the dyestuffs in the crocked areas of the garment will become more severe each time that it is processed.