N.Z. Man’s Process In Use Overseas

Press, Volume CVII, Issue 31548, 9 December 1967, Page 9

N.Z. Man’s Process In Use Overseas

A method devised by a New Zealand scientist for bleaching wools so that carpets made from them do not fade under the influence of light, is now being used by four carpet manufacturers in the United States. On the basis of the most recent reports some 500,0001 b of wool has so far been treated by this process.

Another American company is reported to be using the process for a side-effect not realised when the method was first developed.

The scientist is Mr R. G. Stewart, a research officer on the staff of the Wool Industries Research Institute at Lincoln. His investigations leading to the development of the process were made for the International Wool Secretariat.

Mr Stewart joined the institute in 1959 as the officer re-

sponsible for research on scouring and associated problems, and because of this background of experience he went to the United Stateh4n 1963 when it was thought that a problem of fading being experienced with wool carpets was probably associated with scouring. The carpets had faded when exposed to light for two reasons, said Mr Stewart One was that the wool was not scoured adequately to remove all dirt and the second was that the wool was yellow. The problem was therefore in two sections.

Scouring trials were done in New Zealand and in the United States. Wool was bought in New Zealand and split into two as nearly identical lots as possible. One lot was sent to the United States for scouring by James Lees and Sons, one of the biggest American carpet manufacturing companies; and the other lot was scoured at the Waihi works at Winchester in South Canterbury.

The scouring in New Zealand was done under the supervision of Dr L. F. Story, director of the Wool Indus-

tries Research Institute, and Mr Stewart supervised the trials in the United States. Mr Stewart said the trials showed that under scouring conditions used in the United States, the wool was not as well cleaned as in New Zealand where more water was used in the process, and sorting of wools was superior. Dealing with the problem of yellow colouration in the wool, Mr Stewart said he had devised a method of bleaching wool in the dye bath before dyeing. This meant that if wool was clean when treated, it was whiter. This had been tested, ip.-the laboratory and.theirbn a mill scale, and- finally trials had been conducted in mills in the United States, England, Germany, Belgium and France. No manufacturer in New Zealand was using the process yet, but the cost of the treatment in this country would

be about lie to 2c per lb. There were more effective methods of bleaching, but the cost of applying these would be at least six times higher, A disadvantage of the

method was that it extended the processing time by an hour, but Mr Stewart said he thought that there was a real possibility of reducing the time at present involved. As already mentioned, one American company is using the process ' for the side effects—there is a setting effect on the yarn and a slight increase in harshness of handle. Mr Stewart said that this latter .attribute of the proggjveould ■ hff ’ of beneflt' w New Zealand, as locally produced wools were too soft and New Zealand carpet manufacturers liked to include some 15 to 20 per cent of Scottish Blackface or other type of carpet wool to make it a little harsher in the handle. Use of the process might conceivably result in less wool having to be imported to go into carpet yarns. Mr Stewart said he was hoping to do some trials with a New Zealand carpet yarn manufacturer to see if some use could be made of the effect on the handle of the wool.