Scouring is a process by which all
natural and additive impurities such
as oil,fat,wax, etc are removed to
produce hydropjilic and clean textile
◦ To make fabric highly hydrophilic.
◦ To remove impurities.
◦ To increase absorbency of fabric.
◦ To produce a clean material by adding
◦ To remove natural color.
◦ To remove non-cellulosic substance in
case of cotton.
9. The vegetable oil, which is immiscible with
water, is glyceride of fatty acids. When
such oil are heated with a solution of
sodium hydroxide (Caustic soda) in water,
the oil splits up into its constituents fatty
acid and glycerin. Glycerin is miscible with
water easily and the fatty acids reacts with
sodium hydroxide present in the solution
forming its sodium salt i.e. soap which is
also soluble in water. Thus oil is removed.
12. Wax and non saponifiable oils (Non polar)
are removed by emulsification as they are
immiscible in water (Polar). Normal
washing soap is used as a emulsifying
agent which make emulsion of them. Soap
generated from the saponification process
also act as a emulsifying agent.
After removal of fats and wax by saponification
and emulsification respectively. The remaining
constituents , dust , dirt , particles have to be
removed by a good detergent. Detergents not only
remove dirt particles but also keep them in
dispersed or suspended from in the scouring
solution and does not allow them to settle on the
15. The scouring process brings
following changes in cotton fibres:
i) Oils and fatty acids are converted
ii) Pectin's and pectose are
converted into soluble salts of pectic
iii) Mineral matters are mostly
dissolved or settle down.
iv) Non saponifiable oils are
emulsified by the soluble soaps
generated from the saponificable
v) Additive dirt's are removed.
vi) Residual sizing materials are
broken down into soluble products.