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This is fine Australian Merino wool.
It may seem like greasy, dirty, crinkly stuff
but it has some remarkable properties.
It can produce some of the finest and most sought after fabrics in the world.
It's what happens between the wool coming off the sheep's back
and getting onto your's that makes it so attractive.
What happens of course is that a lot of science and technology
is applied to the raw wool
and there's nothing new in this.
For thousands of years people have been developing techniques for turning the
hair of animals, into textiles.
The first European settlers in Australia were quick to see the potential for wool growing
and before long the country was said to ride on the sheep's back.
Developments such as the invention of mechanical shears in the 1880s
helped expand the industry to the point where Australia became the world's
major wool producer.
Wool is still one of our major industries
with exports worth almost two thousand million dollars a year.
For the clothing industry,
wool has an appeal which synthetic fibres have not been able to match.
That appeal is largely due to the natural qualities of wool.
Qualities that have been enhanced by extensive scientific research.
At CSIRO's Division of Textile Industry in Geelong,
researchers have been finding ways to improve virtually every stage
of wool textile production.
The first step is to wash out the dirt and grease.
It's a process called scouring
and it produces large amounts of effluent
which can be difficult and costly to dispose of safely.
This is a pilot scale plant developed by CSIRO
which offers a new approach to the problem.
It's called Lo-Flo
and produces only a quarter of the usual amount of the liquid waste.
Most of the dirt and grease is removed from the wool in the first washing stage.
The dirty water is then piped into two centrifuges.
One extracts the dirt from the water
and the other the grease.
The water is then returned to the system to continue washing.
Scientists have found that the system not only reduces the amount of effluent
but increases the amount of grease extracted.
The grease, what's more, is a valuable by-product
and is used for the manufacture of lanolin and cosmetics.
The scoured wool is then dried in readiness for the stage
which is called carding.
Carding breaks open the entangled wool
and removes vegetable matter and burrs.
Any remaining burrs, as well as short fibres, are removed by a combing machine.
The wool fibres are now aligned, ready to spinning.
Spinning accounts for about 50% of the costs in yarn production.
Worsted yarns, used for producing suits and skirts fabrics,
are made from long fibres which are spun into a fine yarn.
Single yarns are not strong enough to withstand the stresses of weaving
so two are wrapped around each other in a process called twisting.
Researchers at Geelong
have come up with a simple way of combining spinning and twisting
into a single process with a system they call Sirospun.
It represents savings of up to 40% over conventional systems.
Yet Sirospun is incredibly simple
and can be readily adapted to existing machines.
Spacing devices are fitted to a machine in such a way that two strands of wool
are brought together with twist in each yarn
as well as folding of the two yarns about each other.
A small plastic breakout device is the second essential element.
If one strand breaks
it's important the other doesn't keep spinning by itself.
So the device flips over, prevents the twist being inserted and the yarn breaks.
The operator can then the rejoin the ends and start again.
Since it was introduced in 1981,
Sirospun has been fitted to over 60,000 spindles throughout the world.
The savings of the Sirospun process
have made it economical for many manufacturers to produce
fabrics like these.
Unlike worsteds,
woollen yarns are designed to remain fluffy.
Dying these yarns can take up to two hours of boiling in large vats.
But this radical prototype machine
can achieve a similar result in less than ten minutes.
It continuously dyes a single thread of yarn
at between 300 and 600 meters per minute.
The most difficult stage in the system is application of the dye,
a stage which has foiled previous attempts by German and French companies
to develop continuous dying machines.
The next stage is to fix the dye
which is done in this "J" shaped tube
where the yarn is steamed for about eight minutes.
Inside the tube it looks like a nasty tangle of worms
but miraculously the dyed yarn can be drawn out and wound without trouble,
ready for knitting.
Knitted garments are very versatile
but have always had a major drawback, shrinkage.
Just why wool tends to shrink deserves a closer look.
Under a scanning electron microscope a single wool fibre can be magnified
thousands of times.
Scales on the surface of each fibre
interlock when a woollen garment is washed
preventing the fibres returning to their original positions.
Hence shrinkage.
This Superwash jumper has been treated by the CSIRO Chlorine-Hercosett process
which coats the fibres with resin so they won't catch on each other.
Another process for preventing shrinkage
uses chemical bonds to tie fibres together.
To test the effectiveness of shrink proofing experiments,
researchers subject wool fibres to up to twenty hours continuous washing
in these rotating cubes.
If they can survive this, they can survive anything,
even printing.
Printing patterns onto wool fabrics has always been difficult
and expensive.
But this CSIRO developed process, called Keratrans,
could change all that.
Transfer papers, printed with specially invented dyes
are placed in contact with the wool fabrics.
The wool has been pretreated
to make it more receptive to the dye.
It's by far the simplest and cheapest printing system developed for wool
and it's the first that will allow photographic images
to be printed on to wool fabrics.
At the Division of Textile Physics in Sydney,
a very different but similarly economical system is being developed for
printing wool fabrics.
It uses the technique of jet printing
in which fine jets of dye are literally sprayed onto the fabric.
A computer is used to control both the pattern design and the printing process,
resulting in a system which is both quicker
and more efficient than the usual
silk screen methods.
It's a long way from the good old Merino
to the computer controlled multi-jet printer,
but it's appropriate that Australian ingenuity in the 1980s,
is helping keep one of our oldest industries alive and well
in the international marketplace.