This document provides an overview of nano finishing of textiles, which is an incipient technology. It introduces nano technology and how it can be applied to textile finishing to impart new characteristics. Some key applications of nano finishing discussed include providing water and stain resistance, UV protection, antibacterial properties, wrinkle resistance, and flame retardancy. The document also describes various nano particles that can be used for different functions and synthesis methods like chemical vapor deposition and plasma deposition. In conclusion, nano finishing is still in its early stages but offers exciting opportunities to further innovate textile properties through research.

1. Nano Finishing of Textiles
-AN INCIPIENT TECHNOLOGY

2. Prepared By
MD. Golam Kibria
Lecturer(Wet Processing)
Northern University Bangladesh
B.Sc, M.Sc (Textile Engineering, BUTEX)
Email: kibria.but@gmail.com

3. Overview:
• Introduction
• Nanotechnology
• Textile finishing
• Introduction of Nano finishes in textiles
• Characteristics of Nano finishing in garments
• Synthesis of Nano phase materials
• Nano particles used according to properties
• Nanotechnology applications in textiles.
• Conclusion

4. Introduction:
• The term Nano in Nano technology comes from a Greek word « Nanos » which
means ‘dwarf’. The dictionary meaning of dwarf is abnormally small. On a scale of
10-9 having or involving dimensions of less than 100 nanometer.
• Today, the use of nanotechnology is allowing textiles to become multifunctional.
The emergence of a reality to create, alter and improve textiles at the molecular
level, and to enhance their durability and performance beyond those of existing
textile products, is already apparent due to applications of nanotechnology.

5. Nanotechnology:
• Nanotechnology is the engineering of functional systems at the molecular scale.
• It is the design characterization, production and application structures, devices and
system by controlling shape & size at Nano scale.
• This technology that can work at the molecular level, atom by atom to create large
structures with improved molecular organization.

6. Nanotechnology:
A NANO SIZE PARTICLES
NORMAL 0.03 MICRON SIZE
PARTICLES

7. Textile finishing:
• A finish is done to a fabric after weaving or
knitting to change its appearance, handle &
performance.
• Textile finishing is a term commonly applied to
different process that the textile material
undergoes after pretreatments (singeing,
desizing, scouring, bleaching), dyeing & printing
to enhance their attractiveness and sale appeal as
well as comfort & useful finish.

8. Introduction of Nano finishes in textiles:
The first commercial application of Nano tech in textile and clothing industry is found
in the form of Nano particle (sometimes called Nano bead) through a finishing
process, which is generally known as Nano finishing.
The impact of Nano technology in the textile finishing area has brought up innovative
finishing as well as new application technique.

9. Characteristics of Nano finishing in apparels:
• Nano-processed garments have protective coating, which is water and beverage
repellent.
• Their protective layer is difficult to detect with the naked eye.
• When a substance is manipulated at sizes of approximately 100 nm, the structure of
the processed clothing becomes more compressed. This makes clothing stain- and
dirt-resistant.
• Saving time and laundering cost.
• This technology embraces environmental friendly properties.

10. Characteristics of Nano finishing in apparels:
• Nano-materials allow good ventilation and reduce moisture absorption, resulting
in enhanced breathability while maintaining the good hand feel of ordinary
material.
• The crease resistant feature keeps clothing neat.
• Nano-processed products are toxic free.
• Garments stay bright, fresh looking and are more durable than ordinary materials.
• Adding value to the products.

11. Synthesis of Nano phase materials:
• A large number of methods exist for the synthesis of Nano phase materials.
• They include synthesis from atomic or molecular precursors (chemical or physical
vapor deposition; gas- condensation; chemical precipitation; aerosol reactions;
biological templating), from processing of bulk precursors (mechanical attrition;
crystallization from the amorphous state; phase separation), and from nature.
• It is generally preferable to synthesize nanostructured materials from atomic or
molecular precursors, in order to gain the greatest control over a variety of
microscopic aspects of the condensed ensemble, but other methodologies can
often yield very useful results.

12. Chemical vapor deposition:
• Chemical vapor deposition (CVD) is a chemical process used to produce high-
purity, high-performance solid materials.
• Chemical Vapor Deposition is the formation of a non-volatile solid film on a
substrate by the reaction of vapor phase chemicals (reactants) that contain
the required constituents.
• The reactant gases are introduced into a reaction chamber and are
decomposed and reacted at a heated surface to form the thin film.

13. Chemical vapor deposition Mechanism:
CVD reaction follow the following steps-
• Transport of the reacting gaseous species to the substrate surface.
• Absorption or chemisorption of the species on the substrate surface.
• Heterogeneous reaction by the substrate surface.
• Desorption of the gaseous reaction products.
• Transport of the reaction products away from substrate surface.

14. Plasma deposition:
• Plasma polymerization (or glow discharge polymerization) uses plasma
sources to generate a gas discharge that provides energy to activate
or fragmentgaseous or liquid monomer, often containing a vinyl group, in order
to initiate polymerization.
• Polymers formed from this technique are generally highly branched and
highly cross-linked, and adhere to solid surfaces well.
• The biggest advantage to this process is that polymers can be directly attached
to a desired surface while the chains are growing, which reduces steps
necessary for other coating processes such as grafting.

15. Plasma deposition:

16. Plasma Polymerization Mechanism and Species:

17. Nanoparticles Used according to Properties:
SL
No
Nano particles Properties
01 Silver Nano particles Anti-bacterial finishing
02 Fe Nano-Particles Conductive magnetic properties, remote heating.
03 ZnO andTiO2 UV protection, fiber protection, oxidative catalysis
04 TiO2 and MgO Chemical and biological protective performance, provide self-
sterilizing function.
05 SiO2 or Al2O3 Nano-particles with PP or PE coating Super water repellent finishing.
06 Indium-tin oxide Nano-Particles EM / IR protective clothing.
07 Ceramic Nano-Particles Increasing resistance to abrasion
08 Carbon black Nano-Particles Increasing resistance to abrasion, chemical resistance and impart
electrical conductivity, coloration of some textiles.
09 Clay Nano-particles High electrical, heat and chemical resistance.
10 Cellulose Nano-whiskers Wrinkle resistance, stain resistance, and water repellency.

18. Nanotechnology applications in textiles:
• Due to the advancement of nanotechnology
in the manufacturing of fibers/yarns including
the development of fabric finishes, the
applications and scopes are widespread in the
area of textiles for the last few decades.
• By combining the nanoparticles with the
organic and inorganic compounds, the
surfaces of the fabrics treated with abrasion
resistant, water repellent, ultraviolet (UV),
electromagnetic and infrared protection
finishes can be appreciably modified.

19. Water repellence:
• The water-repellent property of fabric can be improved by creating Nano-whiskers,
which are hydrocarbons and 1/1000 of the size of a typical cotton fiber, that are
added to the fabric to create a peach fuzz effect without lowering the strength of
cotton.
• The spaces between the whiskers on the fabric are smaller than the typical drop of
water, but still larger than water molecules; water thus remains on the top of the
whiskers and above the surface of the fabric.
• The performance is permanent while maintaining breathability. This can be
developed also by the Nano Sphere impregnation involves a three-dimensional
surface structure with Gel-forming additives which repel water and prevent dirt
particles from attaching themselves.

20. Water repellence:
The mechanism is similar to the lotus effect occurring in nature, as demonstrated
in Figure 1. Lotus plants have super hydrophobic surfaces which are rough and
textured.

21. Self-cleaning textiles:
• Super hydrophobic surfaces have considerable technological potential for textile
applications due to their extreme water-repellent properties.
• Finished surfaces with a high contact angle can also exhibit a self-cleaning effect.
Extremely water-repellent super hydrophobic surfaces can be produced using
roughness of nanoparticles combined with hydrophobicity of polymer matrix.
• By adopting such methods, the contact angle of the resultant surface can easily
reach as high as 120°.

22. Self-cleaning textiles:
The textile surface modification methods mainly include sol-gel methods to
fabricate a fluorinated inorganic organic coating on polyamide 6.6 textiles,
grafting poly(acrylic acid) on a polyamide polymer surface and then chains.
Cotton-based super hydrophobic surfaces can be fabricated mainly by
modification of hierarchical Nano scale structure that can confer super
hydrophobicity on the cotton substrates.

23. UV-protective finish:
• The UV-blocking property of a fabric is enhanced when a dye, pigment, de-lust
rant, or ultraviolet absorber finish is present that absorbs ultraviolet radiation and
blocks its transmission through a fabric to the skin.
• To impart UV- protection, several Nano compounds or nanoparticles can be applied
on textile material. Inorganic UV-blockers are more preferable to organic UV-
blockers as they are non-toxic and chemically stable under exposure to both high
temperatures and UV.
• Inorganic UV-blockers are usually certain semiconductor oxides such as TiO2, ZnO,
SiO2 andAl2O3

24. UV-protective finish:
• Titanium dioxide is a photo catalyst; once it is
illuminated by light with energy higher than its
band gaps, the electrons in TiO2 will jump from the
valence band to the conduction band, and the
electron (e-) and electric hole (h+) pairs will form
on the surface of the photo catalyst.
• The negative electrons and oxygen will combine
into O2 the positive electric holes and water will
generate hydroxyl radicals.
• Since both are unstable chemical substances,
when the organic compound falls on the surface of
the photo catalyst it will combine with O2 and OH-
respectively, and turn into carbon dioxide (CO2)
and water (H2O).

25. Anti-bacterial finish:
• For imparting anti-bacterial properties, Nano-sized
silver, titanium dioxide and zinc oxide have been used
so far.
• With the use of Nano-sized particles, the number of
particles per unit area is increased, and thus anti-
bacterial effects can be maximized.
• Nano silver particles have an extremely large relative
surface area, thus increasing their contact
with bacteria or fungi, and vastly improving their
bactericidal and fungicidal effectiveness.

26. Anti-bacterial finish:
• Nano-silver is very reactive with proteins.
• When contacting bacteria and fungus, it
will adversely affect cellular metabolism
and inhibit cell growth.
• It also suppresses respiration, the basal
metabolism of the electron transfer
system, and the transport of the substrate
into the microbial cell membrane
• Hence, Nano silver particles are widely
applied to socks in order to prohibit the
growth of bacteria.

27. Anti-bacterial finish:
• In addition, nano-siIver can be applied to a large range of other healthcare
products such as dressings for burns, scald, skin donor and recipient sites.
• It has been established that a fabric treated with nano-TiO2, could provide
effective protection against bacteria and the discoloration of stains, due to the
photo catalytic activity of nano-TiO2.
• ZnO nanoparticle can also provide effective photo catalytic properties once it is
illuminated by light, by the way it can be employed to impart anti-bacterial
properties to textiles.

28. Anti-static finish:
• ZnO nanoparticles have been used for various applications like UV protection,
mechanical, antibacterial finishes in textiles as discussed earlier. Another area of
application of ZnO is antistatic finishing agent in textiles.
• Nano ZnO with amphoteric surfactant was used to prepare nanometer antistatic
finishing agent and the effect of Nano ZnO concentration, ratio of reactants and
reaction temperature were analyzed by Fan and Junling .
• The cotton fabric and the polyester fabric were both finished by pad-dry-cure process
with the above antistatic finishing agent.
• They found that the charge density of the treated fabric decreased significantly in
comparison with the original piece, showing that the fabric finished with the antistatic
finishing agent was compounded with Nano ZnO producing antistatic performance.
• Through comparison between cotton and polyester treated fabrics, it was observed that
the decline rate of charge density of the latter is more obvious than the former,
revealing that the antistatic effect of polyester fabric finished with nanometer antistatic
finishing agent is better.

29. Wrinkle free finish:
• To impart wrinkle resistance to fabric, resin is commonly used in conventional
methods. However, there are limitations to applying resin, including a decrease in
the tensile strength of fiber, abrasion resistance, water absorbency and dye ability,
as well as breathability.
• To overcome the limitations of using resin, some researchers employed nano-
titaniumdioxide and Nano-silica to improve the wrinkle resistance of cotton and silk
respectively.
• Nano-titanium dioxide was employed with carboxylic acid as a catalyst under UV
irradiation to catalyze the cross-linking reaction between the cellulose molecule
and the acid.
• On the other hand, Nano-silica was applied with maleic anhydride as a catalyst; the
results showed that the application of Nano-silica with maleic anhydride could
successfully improve the wrinkle resistance of silk.

30. Anti pollen finish:
• A few marketing companies around the world have introduced anti-pollen fabrics
and garments.
• It is claimed that particles of 30 nm sizes are attached to the surface of yarns thus
the smoothness of the finish on the surface and the anti-static effect does not let
pollen or dust come close.
• This is achieved by using the polymer which has antistatic or electro conductive
composition e.g. Fluro alkyl – methacrylate polymers).
• It is used in coats, blouses, hats, gloves, arm covers, bedding covers, etc.

31. Flame retardant finish:
• NYACOL Nanotechnologies has been
developed colloidal antimony pent
oxide which has been applied for
flame retardant finish in textile.
• Colloidal antimony pent oxide has
been offered as fine particle
dispersion, for use as a flame
retardant synergist with halogenated
flame-retardants (the ratio of halogen
to antimony is 5:1 to 2:1).
• Nano antimony pent oxide is used
with halogenated flame-retardants
for a flame retardant finish to the
garments.

32. Conclusion:
• Nano finishes being developed for textile substrates are at their infantile stage.
• Nanotechnology is an emerging technology, which is no longer just a vision for the
future as it was generally seen at the end of 20th century. Instead, nanotechnology
is a ubiquitous technology with a lot of potential to impact on every aspect of
modern technology.
• Nanotechnology, with all its challenges and opportunities, is an unavoidable part of
our future.The possibilities with nanotechnology are immense and numerous .
• The researches are filled with technology are beginning to make their mark. The
new concepts exploited for the development of Nano finishes have opened up
exciting opportunities for further R&D.
• In future, one can expect to see many more developments in textiles based on
Nano technology. At last “Nano-Finishing” can be described as a “Synonyms for
Innovation”.

33. References:
• Polymer Nano composites for Multifunctional Finishing of Textiles - a Review.Sorna
Gowri, Luís Almeida, Teresa Amorim, Noémia Carneiro, António Pedro Souto and Maria Fátima
EstevesDOI: 10.1177/0040517509357652 Textile Research Journal2010 80: 1290 originally published
online 9 March 2010 .
• SELECTED APPLICATIONS OF NANOTECHNOLOGY IN TEXTILES , Y. W. H. Wong1,C. W. M.Yuen1, M. Y.
S. Leung1, S. K. A. Ku1, and H. L. I. Lam.
• Functional Nano Finishes ForTextiles ,By: D. Gopalakrishnan & K.G. Mythili .
• Nano-FinishingOfTextiles (TT-03),By:Aravin Prince .P & Raja .P.
• American Vacuum Society (AVS)
• http://en.wikipedia.org/wiki/Plasma_polymerization

34. Any question?