Australian Wool Textile Research (continued)

At this time, research had also commenced on another major problem of wool -insect attack. This entailed building up a colony of insects at Geelong which was maintained and used over many years for research on mothproofing. In 1954 a cheap method of mothproofing[19] was found based on applying small amounts of Dieldrin® to the wool from emulsion, the treatment being unexpectedly fast to dry-cleaning. It was widely used, particularly for carpets, but was discontinued in the early 1970s when it could not meet environmental requirements that were introduced for mill effluents.

® Shell registered trade mark.

Meanwhile, as well as mechanisms of shrink-proofing, the Sydney unit had concentrated its work on development of instruments for the measurement of raw-wool properties and on increasing knowledge of the mechanical and water sorption properties of the fibre. The former work was eventually to play a major role in the development of more efficient marketing systems for raw wool. Early on, however, the research on water absorption led to an apparatus for the rapid testing of the regain (water content)[20] of wool. This work had wide commercial application in commercial transactions, as well as for the control of processing and quality.

Through the 1950s and 1960s, the expertise of the three units was expanded to cover other areas of processing, and this brought further developments.

In 1957, a Geelong development that had wide application was the continuous printing of wool tops. Melange or Vigoureaux printing was a conventional process that required prolonged times of steaming to fix the shade. By suitable alterations to the printing paste,[21] the time of steaming was substantially reduced and a greater depth of shade could be obtained which meant a saving in dye. This was rapidly adopted by local mills and later extended overseas.

Research on mechanical processing at that time was concentrating on the early stages of processing and detailed studies were carried out on the mechanisms and principles in operations such as carding, combing and the drafting of fibres. One of the first practical results of this work was the development of the Comb Control Unit.[22] This was a device that could be fitted to the Noble Comb and would control the output of the machine at any desired level of production. Wool fed to a Noble Comb was controlled by the level of the feed knives. If the amount of wool per unit length of punch sliver and other factors were constant, then the level of the feed knife could be fixed. This ideal situation was not experienced in practice because of elastic and frictional factors in the delivery of the sliver from the punch balls, as well as the lengthwise variations of the amount of wool in the sliver. To compensate for these variables the feed knives level had to be continually adjusted. Traditionally this had been done either manually or by a mechanism with a pre-set rate of change of the level of the feed knife. Neither was satisfactory, and variables as high as 20 per cent were common.

Australian Academy of Technological Sciences and Engineering