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printing - sheetfed 
Rod Urquhart expands on the tiniest science of all " nanotechnology " and explains how it may enhance print enormously. Nano, no it’s not something that Mork from Ork used to greet Mindy with. It is a measure of size, for example in length, one nanometer is a thousand millionth of a metre (in scientific units 10-9m). In fact, the term "nano" comes from the Greek word for dwarf (if you’ve seen the movie My Big Fat Greek Wedding, you’ll know why most words can be derived from Greek!), and if the thickness of this page was one nanometre, a metre would be about eight million magazines piled on top of each other.

The term "nanotechnology" has gained considerable celebrity in the media, and we read of nanotubes of carbon atoms, nano-robots (nanobots), that will deliver medicines to precise locations, and nano-component computers so small as to make Dick Tracey’s wristwatch look gigantic. So why, you may ask, am I writing about this high tech scientific stuff in a printing magazine?

The answer is that some forms of nanotechnology have been in use for years; it is just now that engineering and electronic techniques have become so sophisticated that things can be made or assembled on a very tiny and very precise scale that nanotechnology has grown to be a major influence in scientific research.

Historically, we chemists have been reacting molecules together on a nano-scale since the dawn of alchemy, but the fact that reaction products have not been predictable with absolute accuracy stops us from claiming to have "invented" nanotechnology. However, within CRC Smartprint, nano research is going on that will flower into our industry in the not so distant future.

A year ago I wrote about plasma generation -

"When gases have one or more electrons stripped from their atoms by the application of energy such as heat, electrical discharge, or powerful light (like a laser), they become a soup of atomic residues (ions) and electrons. This is a plasma. Future work will look at grafting new chemical groups onto the surface of paper and polymer films in order to precisely control the properties of the substrate and thereby to generate papers that are selectively easier to print on and will more accurately match the end application. One of the most interesting applications from a global perspective will be to generate new ways of modifying printing substrates to facilitate the removal of inks and coatings from printed surfaces in recycling."

With the clever plasma unit located at the CSIRO Clayton laboratories, plasmas using the gas Argon as a carrier can be generated at atmospheric pressure without the complex sealed chambers needed for the more conventional style of machines that operate at low pressures near vacuum.

Chemicals may be introduced into this ionized cloud of carrier gas, to coat layers only a few atoms thick onto the surface of a substrate (called chemical vapour deposition -CVD), significantly altering the properties of that substrate, truly nanotechnology at work. This is part of the work of Program 2 of the Smartprint CRC.

Another application of nanotechnology is happening right now in a project to develop filler pigments for use in paper coatings that will improve the ability of colours to adhere to them. This is again nanostuff in action, as the basic filler particles are themselves produced by nanotechnological means, and the coating of the chemicals that are there to act as binders are also applied in molecular layers.

We have not yet discussed the fourth research provider for the Centre, the Intelligent Polymer Research Institute at the University of Wollongong (IPRI). IPRI is a specialist research institution under the direction of Professor Gordon Wallace, one of the world’s most eminent scientists in the field of electro-active polymeric materials (plastic-like substances that work with electricity). Such is the standing of Prof Wallace and his team, that IPRI will play a pivotal role in a new $12m Australian Centre of Excellence in Electromaterials Science.

Professor Wallace and his team have developed polymers that can do quite remarkable things, and on a recent visit to Wollongong, he demonstrated some that can be made into inks that are capable of conducting electricity. Before anyone says that there are inks about that already do that, note that current "conductive" inks are simply normal ink carriers with metal articles such as silver dispersed into them to carry current. The IPRI resins are the conductive part, no metals necessary!

IPRI is also developing batteries that resemble a sheet of paper, (imagine powered packages that can carry an illuminated message not too far into
the future).

To digress a little, one fascinating part of this project is to develop nanobatteries that would work with a person’s body fluids to potentially power such items as hearing aids and heart starters of the non-black coffee sort! Another closely related part of Prof WallaceÂ’s research outside of our area is the development of artificial muscles from polymers that stretch and contract when a current is passed through them. These polymers may be further strengthened by the inclusion of nanostrings of reinforcing material. Already materials are being produced that are 20 times stronger than real muscle tissue and the prospects for the future of biomechanics are breathtaking. All of these materials are also built up atom by atom, nanochemical engineering at work.

So, talk of nanotechnology is not just science fiction; thin coatings of carefully placed materials will provide a huge range of capabilities, from more printable papers, containers that can tell a customer if they are out of date, and whether or not the contents of a package has deteriorated in some way, all the way to biomechanical marvels of repair for human bodies.