Chlorine fastness improvers

Excerpt: In today's competitive business of apparel export, characterization of quality is an important and indispensable aspect.

THE colour fastness of reactive, direct, metal complex and acid dye is very poor. Beach towels, swimming suits made of cotton and/or polyamide which are dyed or printed with these dyes are sensitive to chlorine content in pool water and laundry wash liquors. Hence it becomes essential to confirm the fastness to chlorinated pool water of this merchandise. It also encourages to develop products that can enhance the durability and colour fastness of these garments.

In today's competitive business of apparel export, characterization of quality is an important and indispensable aspect. These days, the consumer preference in all fields of textile use, is both., for wash-and-wear properties and wash-fastness at high temperatures. Major source of customer complaint in apparel market generates from colour fastness of textile products.

The colour fastness to chlorinated pool water and sea water is getting more importance in terry towel industry, swimwear and beachwear garments and also for knits and yarn dyed materials. Water in swimming pools generally contain around 5 ppm of available chlorine for disinfecting purpose. Germs and other pathogens can quickly travel from body to body in a swimming pool and chlorine helps to protect our bodies from these pathogens.

Chlorine kills bacteria present in swimming pool water but at the same time it affects swimsuits to an almost irreparable extent. This water containing chlorine can cause discolouration and fading of dye when it comes in contact with dyed garments. The fading or discolouration is due to oxidation caused by the chlorine. Tap water in cities is normally disinfected to kill bacteria with chlorine at around 5 ppm. This water when used for laundering can also cause discolouration or fading of colours.

Water in swimming pool contains about 5 ppm active chlorine, however chlorine fastness is tested upto 100 ppm levels for active swimwear and terry towels. This is because many of us after we get out of the pool do not take care to rinse the suit or towel before drying. This leads to increase in concentration of active chlorine on the fabric and may go upto 100 ppm available chlorine leading to devastating effects of colour fading.

Solutions from Sarex

Sarex has developed specially formulated products Saradye-PLE for cotton and Saradye-429 (MOD) for polyamide which prevents fading of fabric due to exposure of chlorine liquors.

Unique Features of Saradye-PLE

  • Improves chlorinated pool water fastness for sulphur and reactive dyed/ printed cellulosic and cellulosic rich blends.
  • Improves water contact fastness.
  • Improves fastness upto 100ppm available chlorine.
  • Minimum effect on light fastness or tone of the treated material.
  • Does not contain formaldehyde and hence suitable for Oekotex Standard 100.
  • Does not affect handle and absorbency of finished fabric.

Unique Features of Saradye-429 (MOD)

  • Improves fastness to chlorinated pool water of polyamide fabrics dyed with acid dyes.
  • Improves water contact fastness.
  • Improves fastness upto 100ppm available chlorine.
  • Minimum effect on light fastness or tone of the treated material Does not contain formaldehyde and hence suitable for Oekotex Standard 100.
  • Does not affect handle and absorbency of finished fabric.

Application

Application by Padding process

(a) Application by Padding on Finishing Stenter

For Saradye-PLE

  • Padding with 30-50 g/l Saradye-PLE (pH 5-5.5) Dry 140-160oC

For Saradye-429 (MOD)

  • Padding with 25-35 g/l Saradye-429 (MOD) (pH 5-5.5) Dry 140-160oC

 

Application by Exhaust process:

(b) Garment Drum, Winch machines

For Saradye-PLE

  • Prepare solution with 3-5% (w/w) Saradye-PLE
  • Run at 50oC (pH 5-5.5) for 15-20 min.

For Saradye-429 (MOD):

  • Prepare solution with 2.5-3.5% (w/w) Saradye-429 (MOD)
  • Run at 50oC (pH 5-5.5) for 15-20 min.

Standard Test method to evaluate the colour fastness to chlorinated pool water

  • M & S C12A
  • ISO 105-E03:1994
  • AATCC Test Method-162:2002

Author Details

Dr. Naresh Saraf

Sarex Chemicals