The use of nanotechnology in the textile industry is not entirely new; in fact, the market for textiles making use of nanotechnologies is going to be worth an estimated US$115bn in six years' time. In contrast, though, its uptake in garment manufacturing machinery seems to be lagging behind, yet this is exactly what the industry needs believes Prabir Jana.

While nanotechnology applications in textile materials are already taking the world by storm, it's something of a surprise that its potential application in garment manufacturing machinery and processes has not yet been explored.

The tip of the iceberg may be the DLC (diamond-like coating) needle from Triumph Needle Co in Taiwan that reportedly used nanotechnology and was recently launched at the IMB sewn products technology show in Cologne.

What is nanotechnology?
Nanotechnology is simply a manufacturing technology that operates in the range of nanometres, one-billionth of a metre.

In essence, nanotechnology has the ability to bring order to chaos. Under a microscope, even the smoothest crystalline coatings - such as polished chrome - show irregular gaps between the crystals. Over time, this causes these materials to weaken, crack and creep, especially when the structure is under stress.

In general, experts say these gaps can be controlled in one of two ways: by reordering the gaps into a uniform pattern, or by reducing crystal size. Electro-mechanical system technology is used in nanotechnology to produce more refined components and parts.

Application of nanotechnology in surface coating
Arc bond sputtering and super lattice technology are recent developments in the field of surface coating technology.

These techniques combine multiple nano-scale layers of specific metals known for their excellent hardness and chemical resistance, to give the coated material a new and improved structure.

The application of these new coatings on industrial products is designed to change their physical properties, thus improving an individual product's toughness, resistance, performance and durability.

It offers so many benefits to the metal-finishing industry that its growing number of enthusiastic proponents predicts nothing short of a revolution in plating and finishing technology.

Nanotechnology in sewing machine components
One of the current developmental trends among sewing machine manufacturers is to reduce the number of moving mechanical parts and eliminate the use of oil in the sewing head to avoid staining the garments.

Nanotechnology can help improve lubrication among moving machine parts, and their large surface area per unit weight gives better heat dissipation. Even nano-crystal intervention may improve the properties of lubricating oil.

The titanium nitride coated needle Gebedeur, originally introduced by Groz Beckert in 1993, is already a phenomenon in the sewing needle manufacturing industry.

Nearly all Chinese manufacturers are now copying this technology to offer superior hardness properties that penetrate multiple layers of dense fabrics with ease and withstand far more looper contacts without being worn out.

Titanium nitride coated needles are currently produced using Physical Vapour Deposition (PVD) technology, which can produce very small grains in the coating. But the nanoplating process can outperform this vapour deposition process and is applicable to a wider range of work pieces.

Schmetz's Diamond Carboride, launched with lot of fanfare during IMB 2000, offers competitive characteristics but has yet to become commercially popular. One of the impediments of Diamond Carboride is the needle's black colour, which seriously affects the sewing process by making it difficult for the operator to see and thread.

Once again nanotechnology may help by changing the colour of the needle without changing any of its performance properties.

Similarly the steel colour of the presser foot also creates visibility problems with certain dark colour fabrics. Nano applications can create colourful presser feet without any change of surface characteristics.

Surface friction in sewn products manufacturing
Surface finish characteristics play a very important role in the entire garment manufacturing process. Be it fabric to fabric friction, fabric to metal friction or metal to metal friction, all areas can be revolutionised by the application of nanotechnology.

Fabric to fabric friction
During the garment fitting process, there is a compromise between dressing an actual live model and dressing a body form due to the different surface characteristics and resultant friction and ultimate fall of the garment.

Even though companies like Shapely Shadow and Tukaform are trying to solve the problem with their soft body forms, real simulation is a long way off.

But nanotechnology could give the sought-after surface finish to the soft dress forms to emulate human skin.

Even during the sewing process, thread continues to rub against the yarns in a fabric before being set into seams. Nano finishes in sewing thread may open up a new vista here.

Fabric to metal surface friction
Ironing clothes continues to be the most universal finishing process for garments - the other two being pressing and form finishing.

The surface characteristics of the iron base plate and ironing table cover play a very important role in getting required finish, especially with modern lightweight fabrics.

While the iron base should be slippery so it glides over the garment, the table cover should offer friction to hold the item in place. Currently, iron base plates can be covered with Teflon shoes to reduce friction, but no solution is available for the table cover.

Nanotechnology can give the required optimum surface finish to both.

In another example, sewing thread rubs around 70 times when it passes through several thread-guides and finally through the needle eye before being stitched onto fabric. Improved surface characteristics of specific metal parts and the sewing thread may bring may bring sought-after changes in the sewing process.

The inside surface of an attachment also can be nano-plated for frictionless movement of fabric.

In single and low ply CNC cutting, effort is being made to improve technology for drag free cutting of dimensionally unstable fabrics in either a static or dynamic cutting base.

Fabric plies 'stick' to the porous cutter base through suction. The surface characteristics of the material used in the cutter base can be altered accordingly using nanotechnology for improved performance.

The cutting blade edge of straight and band knives and CNC cutting machines can be nano-coated for improved performance.

Metal to metal friction
Apart from gear mesh and other moving parts a sewing machine there are various machine parts/consumables that touch or rub against each other at very high speed leading to wear and tear.

Nano-plating the throat plate, the undersurface of the presser foot, the feed dog teeth, the looper and hook points may bring many bring unprecedented advantages and revolutionise the way fabrics are sewn.

In nano-coatings the size of the grains is much, much smaller, and their number is increased exponentially. The result is that impurities are super-diffused, which is called homogenisation by segregation. Such a coating is said to be stronger and more resistant to stress and corrosion cracking. So when a sewing machine runs at 5000 stitches per minute, nano-coating technology used in the needle, the needle hole in the throat plate, the looper or hook points, the undersurface of presser feet and feed dog can mean the difference between extraordinary and ordinary, or success and failure.

Nanotechnology in the manufacturing process
Buttons are probably the oldest means of fastening apparel, but zippers, Velcro, snaps, buckles and other fastening methods are equally popular. The surface characteristics of these components play a very important role, and using nanotechnology to alter these could bring new benefits.

Similarly, the sharpness and durability of the cutting knife may be improved by the application of nanotechnology. Fraying of the raw fabric edges after cutting is a tremendous problem during handling and requires additional seams to cover the edges. Nano applications to the raw edges during cutting may get rid of the additional seaming operation later.

Nanotechnology could also be used in the adhesive deposition on fusible interlinings to overcome current limitations and improve the suppleness, drape, fall and comfort of fused components.

It could also eliminate the need for interlinings at all, and achieve the same result just by changing and building on existing fibre/fabric properties like handle, air permeability, and the bending rigidity of certain garment components like collars and cuffs.

Nanotechnology has already been used to create stain repellent and self cleaning garments, although the fabric has to be treated so is more expensive. Stain removing is another laborious but important process in garment manufacturing.

Future nano applications may just camouflage the stain as opposed to the current concept of stripping/removing the stain from the garment!

Static electricity causes major problems while cutting and sewing with synthetic fibres in a dry atmosphere, which can also be solved by nanotechnology.

Conclusion
Nanotechnology is opening up options for higher precision and lightening speed in the next generation of apparel and textile processing machinery.

With China already making 60% of the world's sewing machines and having 13 independent or university affiliated centres dedicated to nanotechnology research, the future is no longer for cheap copies of German or Japanese brands.

The coming decade will see the new generations of smart, innovative 'nano-China' equipment ruling the global market.

References
International Journal of Clothing Science and Technology:
http://www.emeraldinsight.com/Insight/viewContainer.do?containerType=Issue&containerId=10731

Change In Control:
http://sec.edgar-online.com/2004/08/10/0001165527-04-000178/Section2.asp

Nanotechnology is on the Verge of Revolutionizing Surface Finishing:
http://www.metalfinishing.com/news/articles/051206_Nanotechnology.htm

Asia Pacific Nanotech Weekly:
http://www.nanoworld.jp/apnw

Cientifica:
http://www.cientifica.com