SCIENCE IN INDUSTRY.

Hawera Star, Volume XLVIII, 23 January 1925, Page 7

SCIENCE IN INDUSTRY.

TRANSFORMING COTTON

By the aid of the chemist, cotton is 'being given qualities that naturally belong to wool or silk. Silk, the aristocrat of textiles, gets the gloss that is ihe envy of the rival fibres from being forced out in a viscous form from the tiny orifices of the spinnerets of the silkworm, solidifying as a- single smooth cylinder a thousand yards long. Cotton, under a. m ieroKcope looks like a rough and scaly rope. Dipping cotton into strong alkali causes the fibres to shorten and thicken and soften. Seventy-five years ago it occurred to an English chemist, John Mercer, to try what could happen if the cotton were not allowed to shrink. So he kept die thread of cloth on stretchers while it was dipped into a solution of caustic soda and left to dry under tension. The lye took the kinks out of the _ cotton and softened its surface and this gave it something of the lustre of silk. So Mercer immortalised himself, and we have had “mercerised” cotton ever since.

A new method of treating cotton lias been invented. This is the opposite of the mercerisation process, for it is produced by acid instead of alkali. Charles Schwartz of the Philana Company at Basle, Switzerland, has found that cotton may be made to resemble its other rival, wool, by immersing it in concentrated nitric acid. The fibres become more curly and their surface rougher, and the fabric assumes the texture of a new material to sight and touch. In wear and warmth and appearance the philanised cloth resembles woollen. The cotton acquires a yellowish tinge, but this may be removed by bleaching. The philanised fabric may be Inter mercerised, and this makes it look like linen.

In England, nitric acid is being applied to the improvement of ramie, an Indian fibre. When ramie under tension is treated with nitric acid, it acquires a silken lustre. When not stretched, it resembles wool. The chemist hak made a new market for cotton waste by dissolving it completely in nitric acid, alkaline sulphide, or acetic acid, and spinning out the viscous fluid into threads of any length, size and shape that he pleases, producing thereby a synthetic- fibre that closely simulates silk in appearance if not in strength. Fifty per cent, of from the chemical laboratory instead cf what seems to be silk nowadays comes from the cocoon. 1