This document discusses antimicrobial finishing on apparels. It defines antimicrobial and antimicrobial agents as chemicals that prevent or inhibit microbial growth. The objectives of antimicrobial finishing on apparels are to prevent cross-infection, reduce odor formation, safeguard fabrics from staining and deterioration, and protect performance. It also discusses types of microbes, evaluation methods, where antimicrobial finishing can be applied, and types of finishes including biostats and biocides.

1. Antimicrobial Finishing
on Apparels
Azmir Latif

2. Antimicrobial
AM means preventing or inhibits the
growth of microorganisms or
microbes

3. Antimicrobial agent
Any chemical which
kills
or
inhibits
the growth of microorganisms / microbes
is known as AA

4. OBJECTIVES OF AM FINISHING
1. Preventing cross infection by microorganism
2. Reducing the formation of odour by protecting
metabolism of microbes
3. For safeguard of apparel and textile products from
staining, discoloration and quality deterioration
4. Protecting performance of apparels

5. Microbes cause cross infection
by microorganism and development odour
where the apparel is worn next to skin.
In addition, the staining and loss of the
performance properties of textile substrates
are the results of microbial attack.

6. WHY AM FINISHING FOR APPARELS
The inherent properties of the textile fibres provide room for the
growth of micro organisms. Besides, the chemical processes may
induce the growth of microbes. Humid and warm environment still
aggravate the problem.
Apparels (like undergarments, sportswear, etc), medical bedding
mattresses & covers need antimicrobial finish.
Again, the consumers are now increasingly aware of the hygienic
life styles and there is a necessity for a wide range of apparel
products finished with advanced technological antimicrobial
finishes.

7. WHAT ARE MICROBES ?
A variety of micro organisms like bacteria, fungi, algae
and viruses. Microbes are the tiniest creatures not
seen by the naked eye.
Bacteria are unicellular organisms, which grow very
rapidly under warmth and moisture.
Sub divisions in the bacteria family are Gram positive
(Staphylococcus aureus), Gram negative (E-Coli), spore
bearing or non-spore bearing type.
Some specific types of bacteria are pathogenic and
cause cross infection.

8. MICROBES
Fungi, molds or mildew are complex organisms with slow growth
rate. They stain the apparel fabric and deteriorate the
performance properties of the apparel fabrics.
Algae are typical micro organisms, which are either fungal or
bacterial. Algae require continuous sources of water and sunlight
to grow and develop darker stains on the fabrics.
Dust mites are eight legged creatures and occupy the household
textiles such as blankets bed, pillows, mattresses and carpets.
The dust mites feed on human skin cells and liberated waste
products can cause allergic reactions and respiratory disorders.

9. Related Terms
1. Antibacterial agent :
Any chemical which kills bacteria (bactericide) or interferes with
the multiplication, growth or activity of bacteria (bacteriostat).
2. Antifungal agent :
Any chemical which kills or inhibits the growth of fungi.
3. Antimicrobial Activity :
A measure of effectiveness of an antimicrobial agent.

10. Terms
4. Bacterial resistance :
Resistance to the development of bacterial growth
and accompanying odors, resulting from bacterial degradation
of fibres.
5. Mildew resistance :
Resistance to the development of unsightly fungal growths
and accompanying unpleasant, musty odors on materials.
.

11. Methods of AM Finishing
The antimicrobial agents can be applied to the apparel and textile
substrates by-
1. Exhaust
2. Pad-dry-cure
3. Coating
4. Spray and
5. Foam techniques
The substances can also be applied by directly adding into the fibre
spinning dope or can be applied during the dyeing and finishing
operations.

12. Applying Techniques of AM Finishes
(1) Treating with resin coating on apparel surface, or
(2) Cross-linking on apparel surface, or
(3) Use of graft polymers, or co-polymerization
(4) Chemical modification of the apparel fabric
(5) Micro encapsulation of the antimicrobial agents
with the fibre matrix

14. Commercial Antimicrobial Agents
Ciba markets Tinosan AM 110 as a durable antimicrobial agent for
textiles made of polyester and polyamide fibres and their blends
with cotton, wool or other fibres.
Tinosan contains an active antimicrobial (2, 4, 4'-Trichloro-2' -
hydroxyl-dipenylether) which behaves like a colorless disperse
dye and can be exhausted at a very high exhaustion rate on to
polyester and polyamide fibres when added to the dye bath.
Clariant markets the Sanitised range of Sanitized AG, Switzerland
for the hygienic finish of both natural and synthetic fibres. The
branded Sanitised range function as a highly effective
bacteriostatic and fungistatic finishes and can be applied to
textile materials such as ladies hosiery and tights.

15. Durability of Antimicrobial Apparels
Temporary antimicrobial properties in apparels
are easy to achieve in finishing but readily lost
in laundering.
Temporary antimicrobial textiles are useful only
for disposable materials.
Durable antimicrobial function is quite challenging
to achieve and can last more than 50
machine washes.

16. Evaluation of AM Finishes
Methods for evaluating or determining the
effectiveness of antimicrobial finishes can be divided
into two types:
1. Quantitative and
2. Qualitative
In quantitative method, the number of bacteria, still
living after an opportune contact time, is counted.
In both the quantitative and qualitative tests, it is
essential to measure the bioactivity of a reference
control sample without antimicrobial properties.

17. Where Can be Applied-1
Sportswear/leisurewear/workwear:
To prevent bad odour produced by the
bacterial decomposition of sweat and other
body fluids.
Undergarments :
To control the growth of bacteria which thrive
on suitable body temperature and moisture
conditions, leading to skin diseases.

18. Applied-2
Socks:
To make them free from unpleasant odour
by controlling the growth of microbes.
Shoes:
To avoid shoe odour and the stains on the
shoelaces caused by bacterial growth, especially
in rainy season.
Textiles in Museums:
To preserve textile monuments from microbial attack.

19. Applied-3
Sized Fabrics :
To protect microbial growth due to the presence
of warp size.
Medical Textiles :
To impart antimicrobial properties on wound
dressings and get freedom from microbes/
pathogens from apparels & textiles used in
hospitals, nursing homes, medical and
research facilities, and veterinary clinics
for protection against infectious diseases.

20. Washing Vs AM Finishes
Normal home-washing of apparels & textiles, which is generally
under mild conditions, does not completely remove the microbes.
In order to eliminate microbes, very severe laundering conditions,
e.g., a temperature of 95 °C and strong detergents followed by
bleach, are essential.
Any surviving microbes can quickly multiply again at each further
wearing. This can be avoided by the application of antimicrobial
finishes.

21. Types of AM Finishes
Finishes are two types:
1. Biostats, i.e. bacteriostats, fungistats
2. Biocides, i.e. bacteriocides, fungicides
Antimicrobial is an agent that works against microbes. It can
either inhibit their growth and reduce the undesired by-products
or kill them together.
Agents which inhibit the growth of microorganisms and do not kill
them are known as biostats, i.e. bacteriostats, fungistats.
Agents which actually kill the microorganisms are known as
biocides, i.e. bacteriocides, fungicides.

22. Mechanism of Biocides
All antimicrobials do not work in the same manner. The actual
mechanism of control of microorganisms by antimicrobials is
extremely varied.
They leave the textile and chemically enter or react with the
microorganism acting as a poison. Like an arrow shot from a bow
or a bullet shot from a gun, they are used up in the process of
working, or complexed with other chemicals in the process.
Again some antimicrobials consists of molecules that are
chemically bound to fibre surfaces and remain affixed to the
substrate, killing microbes as they contact the surface.

23. Antimicrobial Finishing Methodologies & Mechanisms of
antimicrobial finishes
A variety of chemical finishes have been used to produce
textiles with demonstrable antimicrobial properties. These
products can be divided into two types based on the mode
of attack on microbes.
One type consists of chemicals that can be considered to
operate by a controlled-release mechanism.
The second type of antimicrobial finish consists of
molecules that are chemically bound to fibre surfaces.

24. Controlled-release mechanism
The antimicrobial is slowly released from a reservoir either on the fabric surface or in
the interior of the fibre. This ‘leaching’ type of antimicrobial can be very effective
against microbes on the fibre surface or in the surrounding environment. However,
eventually the reservoir will be depleted and the finish will no longer be effective. In
addition, the antimicrobial that is released to the environment may interfere with other
desirable microbes, such as those present in waste treatment facilities.
Molecules that are chemically Antimicrobial finishes bound to fibre surfaces
These products can control only those microbes that are present on the fibre surface,
not in the surrounding environment. ‘Bound’ antimicrobials, because of their
attachment to the fibre, can potentially
•be abraded away
•or become deactivated
•and lose long term durability.
•Mechanisms of antimicrobial finishes
Antimicrobial finishes that control the growth and spread of microbes are
moreproperly called biostats, i.e. bacteriostats, fungistats. Products that actually kill
microbes are biocides, i.e. bacteriocides, fungicides.

25. Bound antimicrobials
Several antimicrobial finishes that function at fibre surfaces
One popular product is based on octa-decyl-amino-dimethyl-
After application, a curing step is required to form a siloxane
•antimicrobial part of the molecule (the quaternary nitroge
• and provides the necessary durability to laundering.
Another bound finish has been developed with PHMB, poly-hexa-
methylene biguanide

26. Test Method:

28. Conclusion
Cotton fabrics are highly popular because of their excellent
properties such as regeneration, bio-degradation, softness,
affinity to skin and hygroscopic properties. When in contact
with the human body, cotton fabrics offer an ideal environment
for microbial growth due to their ability to retain oxygen,
moisture and warmth, as well as nutrients from spillages and
body sweat. Therefore, an anti-microbial coating formulation
(Microfresh and Microban together with zinc oxide as catalyst)
was developed for cotton fabrics to improve treatment
effectiveness. With advent of new technologies, the growing
needs of the consumer in the wake of health and hygiene can
be fulfilled without compromising the issues related to safety,
human health and environment. The consumers are now
increasingly aware of the hygienic life style and there is a
necessity and expectation for a wide range of textile products
finished with antimicrobial properties.