Introduction Of Finishing
And Resin Finishing
I M.Tech ( Textile Technology)
INTRODUCTION& IMPORTANCE OF
The ultimate aim of a finishing process is to develop
and or modify the fibers or finishes for conventional
synthetic fibers so that they give the comfort of
natural fibers , the richness of animal fibers
A finishing process in which a desired quality or
qualities are imparted to fabric in order to improve the
appearance, to affect stiffness, weight, elasticity, or
softness, to facilitate care, or to protect the wearer.
Examples include calendaring, durable press
finishing, water and oil repellency, and softening
As the name implies, it is the last step or the process
in the method of conversion of fiber into fabric
which is in the marketable or useable form.
After finishing only the steps of inspection and
packing are left to make the fabric ready for
shipment or marketing.
FINISHING GIVES THE FOLLOWING
Improved appearance – luster ,whiteness etc.,
Improved feel which depends on the handle of the
fabric and its softness, suppleness, fullness etc.,
It improves the wearing qualities – Non soiling
It gives special properties required for particulars
uses – water proofing, Flame proofing etc.,
It covers the faults of the original cloth
It increases the weight of the fabric
It increases the sale value of the material.
It improves the serviceability of the fabric.
Hence finishing is essential for a textile good before
they are put on the market.
TYPE OF FINISH
Chlorination of wool
All are permanent
Oils, Fats &
E.g., Synthetic resin
(Crease resistance, Wash
& wear Durable press)
China clay (Stiff)
cellulose ether (stiff)
Finishing Is Commonly Divided Into Two
In chemical finishing, water is used as the medium for
applying the Chemicals.
Heat is used to drive off the water and to activate the
It is considered a dry operation even though moisture
and chemicals are often needed to successfully
process the fabric. Calendaring
Type Of Finish (Durability)
Finishing mainly falls into three groups;
1. Temporary finish
2. Permanent finish
3. Semi-permanent finish
Cotton is mainly selected for apparel purpose because of its
durability, ability to withstand the rough laundering treatments
especially under alkaline conditions, good perspiration absorption
characteristics, and comfort during wear and ability to take up a
wide range of dyestuffs.
However, proneness to creasing under slight crushing and retention
of the crease for a long time give cotton garments a poor rating
during actual wear.
The ability of a fabric to resist the formation of crease or wrinkle
when slightly squeezed is termed as crease resistance.
The ability of a fabric to recover to a definite degree is called crease
recovery of the fabric.
Obviously Resin Finishing is the process of bringing out a
special property of „crease recovery‟ to Cotton.
Resin finishing often known by various fancy terminology is an
important process of textile processing.
Resin finishing quite often called
“ Wash & wear finish”
“Anti crease finish”
“Crease resistant finish”
“Durable press finish”
“ wrinkle free finish”
is gaining importance today
Resins are cross linking agents, which form covalent
bond on reaction with –OH groups of cellulosic
materials in acidic medium at a pH of 3-4.
RESINS MAINLY FALL INTO TWO GROUPS
Deposition type of resins
Cross linking type of resins
Deposition type of resins
This type of resins is deposited on the fabric as
surface coating. No reaction will take place
between the fiber and resin. They include
Urea formaldehyde resin
Cross Linking Type Of Resins
o These types of resins chemically react with the fiber and
cross link the fibre molecules.
o The type of finish obtained is durable and much better than
o They are also known as N – Methylol compounds as the
Methylol groups (-CH2 OH) are attached to the nitrogen.
The cross linking compounds are commonly called resins,
but the term pre condensate is correct. The pre
condensates further polymerize to form resins.
The following are some of the cross liking agents mostly
used for crease resistant finishing.
DMU (Dimethylol Urea )
DMEU (Dimethylol Ethylene Urea)
DMDHEU (Dimethylol Dihydroxy Ethylene Urea)
DMPU (Dimethylol Propylene Urea)
TMM ( Trimethylol melamine/ Melamine formaldehyde
The main objective of resin finish Keep the fabric flat and smooth and
Free from undesirable creases
It improves the Crease Resistance and Crease Recovery property
It reduces the shrinkage of the fabric during laundering
It imparts a smooth and quick drying property
It improves Resilience, Handle and Draping quality
It improves the weight and Dimensional stability
It increases the strength of RAYONS in both wet and dry state
It gives resistance to degradation by light and laundering
It improves the fastness to Light and Washing of many dyestuffs
It prevents the Inter molecular slippage in the fiber core
It becomes partially water proof and Rot proof
It decreases the Tensile strength and Tear strength
It decreases the Abrasion resistance
It gives an unpleasant odor
It gives unwanted Harsh and Stiff feel
It turns the fabric yellow after chlorine bleaching
WHY COTTON FORMS CREASES ?
We also understand that Elastic materials like rubber do not form
We know that rigid materials like metals do not form creases.
Cotton is not
* RIGID and therefore bends and the deformation results in as
ELASTIC and therefore can not regain its original shape and
position after deformation.
* It is clear that when a load is applied on cotton material, since it is
not rigid will bend and deformation that takes place results in as
CREASE and since cotton is not a elastic material it can not regain
its original shape and position and hence the deformation that
resulted remains as SET CREASE.
MECHANISM OF CREASING
Why do some fabrics wrinkle and others don't?
Close examination of this question reveals a relationship
between moisture absorption and wrinkling. Wool and cotton
fabrics wrinkle, both fibers absorb water. Polyester and nylon
fabrics are more resistive to wrinkling, they absorb much less
than the other two.
To understand wrinkling of cellulose fibers, consider the stress
and strain forces within the cellulosic chain.
The stretching stresses a t the outer reaches of the bend
provide lateral forces to adjacent polymer chains which can
cause them to move.
MECHANISM OF CREASING
Under stress, the hydrogen bonds between
adjacent cellulose chains can break allowing the
chains to slip past each other.
The inner polymer chains are under compressive
stresses – also providing lateral forces.
New H-bonds can form as the hydroxyl groups reassociate with different partners.
Having done so, there are no forces to pull the
neighboring chains back to their former position.
The stressed shape of the fiber is just as stable
now as was the original shape.
THEN HOW TO MAKE COTTON
CREASE RESISTANT ?
It is clear now that the weak Hydrogen bonds gets disturbed
during the course of washing and on drying they try to
rearrange and reform giving rise to creases.
From the mechanism of creasing either we have to
Prevent disortion of hydrogen bonds.
Make cotton rigid- which for obvious reasons
Make cotton Elastic- which for obvious
reasons not feasible.
Therefore the only way left out will be to prevent disortion of
Hydrogen bonds which is being perfectly carried out by
means of BLOCKING the Hydrogen bonds forming groups
by means of cross linking of –OH groups of cellulosic
Various Catalysts have been suggested and
reported in literature which exhibits their own
influence on the fixation of resin and in turn on the
The catalysts mainly are Acid liberating agents
which liberates the required acid by decomposition
during curing process and thus maintains the pH. Of
the various catalysts, Magnesium Chloride, DiSodium Hydrogen Phosphate, Di-Sodium DiHydrogen Phosphate, etc are popular. For
commercial purposes Magnesium Chloride is only
used from the cost point of view. Even though
differences in the CRA obtained are reported with
different catalysts usage in the padding liquor,
commercially they are not much important.
As the concentration of resin increases in the pad
bath the CRA of the resultant product increases.
(Mole x 102 / 100G Fabric)