mercerization:

• application of a highly concentrated caustic treatment (NaOH) to cellulose fibers to improve luster, water absorbance, dye yield and fiber strength
  • apply treatment to cotton or cotton blends
  • cotton will swell during treatment

cotton fiber cross sections

• mercerization treatment swells cotton fiber cross section from a ribbon-like to a round shape

• resultant fiber changes

  • fibers will “untwist”
  • lumen mostly disappears
  • fibers become more round, smooth and uniform

  

advantages of mercerizing cotton

• improved color yield and reactivity
  • ~35% increase in color
• improved appearance after dyeing
  • obscures motes and immature cotton
• improves strength (~35%)
• improves luster (if done under tension)
• improves fabric smoothness
• increased absorbency

mercerization process in detail

• apply 22-25% NaOH at 100% WPU
  • anionic penetrant often used
• dwell on timing cans
  • 30-60 seconds
  • RT (room temp) to 160F