by [TC]²
Nanotechnology in Apparel Manufacturing: The New Horizon
By: Prabir Jana
Introduction
Since I wrote the “Crossbreeding of Technology” last year, I am trying to think weird. The developments in sewn products technology and processes are still sector specific. Apart from IT intervention no other technology sector seems to be attracting attention in the industry. Thinking out of the box again gave birth to this article. While nanotechnology application in textile materials is already taking the world by storm, it is surprising that its potential application in garment manufacturing machines and processes have not been explored yet. The tip of the iceberg may be the recently launched (at IMB 2006) and not-so-hyped DLC (diamond like coating) needle from Triumph Needle Co. in Taiwan which has reportedly used nanotechnology.
What is Nanotechnology?
Nanotechnology is a manufacturing technology in the 102 nm to 0.1nm range and an electro-mechanical system technology is used in nanotechnology to produce more refined components and parts to integrate microelectronic circuit and controller systems. 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 to have excellent hardness properties and chemical resistances, into consecutive films that give the coated material a new and improved periodical 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 of plating and finishing technology.
Nanotechnology Application in Sewing Machine Components
One of the current developmental trends among sewing machine manufacturers is reducing the number of moving mechanical parts, noise and oil usage. Nanotechnology can help improve lubrication among moving machine parts that have a large surface area per unit weight, thus creating better heat dissipation. Even the nano crystal intervention may greatly improve lubricating oil properties.
Titanium nitride coated needles (Gebedeur, originally introduced by Groz Beckert in 1993) are already a phenomenon in the sewing manufacturing industry. Nearly all Chinese manufacturers are now copying the technology to offer superior hardness properties that can 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 Vapor Deposition (PVD) technology, which can produce very small grains in a coating. But a nano-plating process can out perform the vapor deposition process and is applicable to a wider range of working pieces.
Schmetz’s Diamond Carboride, launched with lot of fanfare during IMB 2000, offered competitive and promising characteristics, but has yet to become commercially popular. One of the serious impediments of Diamond Carboride is the black color of the needle, creating low visibility, which seriously affects the sewing process as well ease of needle threading by the operator. Once again, nanotechnology may help by changing the color of the needle without changing any performance properties. Similarly the steel color of the presser foot also creates visibility problems with certain dark colored fabrics. A nano application can create colorful presser feet without any change to surface characteristics.
Surface Friction in Sewn Products Manufacturing
Surface finish characteristics play a very important role in the entire garment manufacturing process. Inter surface friction determines many functional as well as aesthetic qualities of the processes. Be it fabric to fabric friction, fabric to metal friction or metal to metal friction, all areas can be revolutionized by nanotechnology.
Fabric to fabric surface friction
Using dress forms as opposed to a live model during the garment fitting process can create compromises. The different surface characteristics between the dress form and garment ultimately affects the drape of the garment. Even though companies like Shapely Shadow and Tukatech are trying to solve the problem through soft body forms, ideal simulation has not been achieved. Revolutionary nanotechnology can give the sought-after surface finish to the soft dress forms to emulate actual human skin.
Even during sewing, the sewing thread continues to rub against yarns in the fabric. Nano finishes for sewing thread may open up a new vista.
Fabric to metal surface friction
Ironing continues to be the most universal finishing process for garments (the other two being pressing and form finishing). Surface characteristics of the iron base plate and table cover play a very important role in producing the required fabric texture—especially with modern light weight fabrics. While the iron base should be slippery, the table cover should offer friction. Currently iron base plates can be covered with TeflonÒ to reduce friction, but there is no solution available for the table cover. Revolutionary nanotechnology can give the required optimum surface finish to both.
Sewing thread passes through several thread-guides and finally through a needle eye rubbing 70 times before being stitched into the fabric. Improved surface characteristics of specific metal parts as well as sewing thread may bring sought after changes in sewing processes. The inside surface of attachments also can be nano-plated for frictionless movement of fabric.
In single and low ply CNC cutting there has been an effort to improve technology for drag free cutting of dimensionally unstable fabrics for both a static and dynamic cutting base. Fabric plies are stuck to the porous cutter base through suction. Surface characteristics of the material used in the cutter base can be altered using nanotechnology for improved performance. The cutting blade edge of a straight and round knife and CNC cutting machines can be nano-coated for improved performance.
Metal to metal friction
Apart from gear mesh and other moving parts inside the machine there are various machine parts/consumables that touch or rub against each other at very high speeds leading to wear and tear. Nano-plating of the throat plate, undersurface of the presser foot, teeth of the feed dog, looper and hook points, etc. may bring many unprecedented advantages and revolutionize the way we sew fabrics.
“In nano-coatings the size of the grains is much, much smaller, and their number is increased exponentially. The result is impurities are super-diffused, which is called homogenization 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 in needle, needle hole in throat plate, looper or hook points, under-surface of presser feet and feed dog can mean the difference between extraordinary and ordinary, or success and failure, in other words”. – Prabir Jana
Nanotechnology application in manufacturing processes
Buttons are probably the oldest means of fastening a garment. Zippers, Velcro, snaps, buckles and other numerous ever-evolving fastening methods are becoming popular for their functionality and non-compromised performance. The surface characteristics of these components play a very important role. Nanotechnology offers numerous possibilities by altering the surface characteristics to achieve unprecedented benefits.
Similar to sewing machine components, the sharpness and durability of the cutting knife may be improved by nano applications. Fraying of raw edges after being cut is a tremendous problem during handling and requires additional seams to cover the edges. Nano application of raw edges during cutting may eliminate the need for additional seaming operations.
Nanotechnology applications for adhesive deposition fusible interlinings may overcome many current limitations and revolutionize the suppleness, drape, fall and comfort of fused components. In the future, nanotechnology may eliminate the need for interlining applications. It may be possible to build into the fibre/fabric and ultimately the garment components (cuff, collar etc.) properties like hand, air permeability and bending rigidity.
Stain repellent nano coatings require the fabric to be treated, thus making the fabric expensive. The removal of stains is another painful but important process in garment manufacturing.
Future nano application may just camouflage the stain rather than the current concept of stripping/removing the stain from the garment! - Prabir Jana
Static electricity causes major problems during cutting and sewing of synthetic fibers, especially in a dry atmosphere. This also can be solved by a nanotechnology application.
Conclusion
With development in machinery manufacturing technology at a watershed, the requirement now is for innovative breakthrough technology. I believe that nanotechnology is opening up a demand for higher precision, greater density and lightening speed combined with the intellectualization and miniaturization to progress into the next generation of apparel and textile processing machinery.
With China already making 60% of the global sewing machines, and 13 independent and/or universities with dedicated centers for nanotechnology research, the future is not any more a cheap copy of German or Japanese brands. The coming decade will see the new generation of smart, innovative “Nano-China” machines which will rule the global market.
References
http://www.emeraldinsight.com/Insight/viewContainer.do?containerType=Issue&containerId=10731
http://sec.edgar-online.com/2004/08/10/0001165527-04-000178/Section2.asp accessed on 06 December 2005
http://www.metalfinishing.com/news/articles/051206_Nanotechnology.htm
Asia Pacific Nanotech Weekly, www.nanoworld.jp/apnw accessed on 27th February 2006
www.cientifica.com www.cientifica.com
Mr. Prabir Jana, a visionary in technology development and management in apparel manufacturing, has been associated with National Institute of Fashion Technology, New Delhi since 1993. He is currently pursuing doctoral research on Supply Chain Dynamics in Indian Textile and Clothing Industry jointly with Nottingham Trent University, UK.
July 2006