Based on a review article written by: Tsuyoshi Sekitani, Hiroyoshi Nakajima, Hiroki

Maeda, Takanori Fukushima, Takuzo Aida, Kenji Hata and Takao Someya which was

published on 10th May, 2009 in Nature Material this presentation aims at introducing

what printable elastic conductors are and how they can be used in the varied field of

semiconductors for the better use of humanity.

Stretchability will significantly expand the applications scope of electronics,

particularly for large-area electronic displays, sensors and actuators. Unlike for

conventional devices, stretchable electronics can cover arbitrary surfaces and

movable parts.However, a large hurdle is the manufacture of large-area highly

stretchable electrical wirings with high conductivity. Here, we describe the

manufacture of stretchable active matrix OLED display using printable elastic

conductors.

Active-matrix is basically a type of addressing scheme (pixel state) used in flat panel

displays like LCD TV screens.

Recently new technologies have been emerging in the field of “stretchable”

electronics like the development of elastic electrical wiring that is both highly

conductive and highly stretchable . Although there have been examples of these kind

of materials been made like graphene films coated with metal; problem that has arose

is to find a procedure to make such materials larger in size. One solution to this

problem that has been provided by the authors in this article is to develop printed

elastic conductors which are extraordinarily conductive and use that to construct a

rubber-like stretchable active-matrix display.

What do one exactly mean by a printed elastic conductor?

The authors provide a technique of producing stretchable OLED’s by using the principle of

direct printing technologies i.e. printable inks that have high conductivity and stretchability

to make printed elastic conductors which consists of fine SWNT bundles uniformly

dispersed in a highly elastic fluorinated rubber matrix which is quite viscous. The

chemically stable SWNTs (high purity) act as highly conductive dopants and help in

forming well developed conducting networks in rubber.

Advantages of printed elastic conductors

No requirement of any kind of extra coating of metal unlike other conductors (e.g.

graphene films)

No requirement of any huge mechanical process unlike others like wavy thin metals

It can stretch by a huge margin (118%)

Has an extraordinarily high conductivity (102 S/cm)

Basic idea of organic light emitting diode

After making the elastic conductors the authors explains a process of manufacturing

Organic LEDs and organic driving cells separately on PDMS sheets which are then

joined together to form a highly stretchable display.

An active matrix was then fabricated on a flexible polyimide film using a special process

called vacuum evaporation.

By integrating the active matrix and organic LEDs using printed elastic conductors a

stretchable active-matrix Organic LED display was finally manufactured.

Bending or crumpling causes no mechanical or electrical damage because of the

excellent conductivity and mechanical durability of the printed elastic conductors ,

organic transistors organic LEDs manufactured on the special rubber.(PDMS rubber)

The stretchable materials and manufacturing technology like printed

electronics used in this study can also be used to create other types of

useful electronics such as rubber-like electrical artificial skin with a

stretchable active matrix and pressure sensors. The combination of

stretchable sensors and displays can be used to create real, tangible

displays and user-friendly human-machine interfaces on all kinds of

surfaces and of shapes. Active research is still being done in this regard

by many international electronic companies like Visionox and Samsung.

Research on finding materials regarding these types of printed

conductors is going on in full flow by well-known scientists in major

universities like Stanford University , Yale University etc.

Thus we can find that, the printable elastic conductor developed in this work enables the

construction of electronic integrated circuits that can spread over any surface including

curved and movable parts. This would significantly expand the areas where electronics

can be used. This is an important step towards the development of the infrastructure for

the coming era of ambient electronics in which a large number of electronic devices such

as sensors and display networks function as user friendly human-machine interfaces that

can be used in daily life to enhance security, safety and convenience and also as

wearable technology.

REFERENCE WEBSITES

www.nanowork.com

www.cse.whk.edu.hk

www.ftp.priceton.edu

www.en.wikipedia.org

www.86wiki.com

www.ncbi.nim.gov/pubmed

www.m.wisegreek.com/whatisjetmilling

www.users.wfu.edu

www.fredlake.com

www.ieexplore.ieee.all

www.rubberworld.com

www.freedictionary.com

www.rsc.com

www.vipsmail.1.blogspot.in

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