Soil Release Finish and Antistatic finish
What is Soil Release Finish?
Durable press fabrics containing polyester fibres are known to show tendency to retain stains and also attract soil from the wash liquor during washing. This is due to hydrophobic nature of these fabrics. Various soil-release agents have been developed. These are described as durable film forming polymers containing polymer groups which are capable of hydrogen bonding with water. These finishes are applied by a pad-cure process along with the resin.
Treatment of synthetic fibers with hydrophilic polymers is in general called soil release finishing, which makes the soil adhereing the hydrophobic fibers more accessible to water and easily removable.
The fluorocarbons use dfor this purpose are dual action fluro polymers containing hydrophilic hydrocarbons as well as perfluroalkyl groups. These finishes are generally applied to synthetic fibers which are generally prone to soiling.
When a finished fabric is immersed in a liquid, hydrophilic hydrocarbon groups orient towards polar aqueous environement and flurocarbon groups collapse below the surface promoting the release of stains. Thus easy removal of stains takes place when the fabric is subjected to laundering.
This finish can be applied by pad-dry-cure method along with durable press finish. Although these finishes are the most expensive ones, they are the most widely used because of ther performance, comfortability with durable press finish and not side effects.
During spinning, weaving and finishing, textile fibres, yarns and fabrics are subjected to friction. Static electricity is thus generated on the fibre. Polyester fibre has low conduction hence it accumulates static electricity. Static electricity gives rise to a number of problems. For instance, the operator at the delivery end of a stenter may get electric shocks because of static electricity. Garments made of polyester fibres attract soil during normal wear and also have a tendency to cling to the body of the wearer.
Non-durable antistatic agents are usually hygroscopic surface-active materials, closely allied in composi6on to softeners and wetting agents. A permanent antistatic finish can be given by using a combination of a cationic and an anionic compound.
Cationic quaternary ammonium compound - 3-4%
Acetic acid (30%) - 0.5-1 cc/l
Treat the fabric with the above composition for 10-20 min at 70'C (in a jigger). Then add (anionic alkyl sulphate) - 1.6-2.2%
Continue treatment for another 10-20 min. Dry and cure if required.