WOOL FROM MILK

Wairarapa Times-Age, 14 December 1938, Page 3

WOOL FROM MILK

NEW USE FOR CASEIN. DISCOVERY IN AMERICA. A synthetic fibre having the appearance of wool can be manufactured from casein, a milk by-product, by a process devised by Stephen P. Gould and Earl O. Whittier of the Bureau of Dairy Industry, United States Department of Agriculture. The process is similar to that used in making viscose rayon from cellulose, -and public service patents, applied for by the Bureau, are pending. In Italy, where a somewhat different process for making casein fibre was announced three years ago, production is already on a commercial scale. Most of the fabrics, however, are half synthetic fibre and half wool. To make the fibre, casein is softened in water and dissolved in a solution of caustic alkali. It becomes a thick, sticky mass, and is carefully worked into the proper consistency by aging, addition of modlifying agents, and dilution. The mass is then forced through multiple spinnerets of the kind used in making rayon. The fibres are separated and hardened in an acid bath containing formaldehyde and modifiers. Synthetic fibre produced in this manner has a chemical composition almost identical with wool except for a lower sulphur content. The fibre .is faintly yellow in colour and closely resembles best grade, thoroughly washed and carded Merino wool, the finest size marketed. The casein fibre has the characteristic fine kink of natural wool, and may be blended with it to make a product that has the resilience of pure wool. Synthetic fibres with this, kinky structure have been made from plant materials recently, but since they do not take wool dyes, they are not as desirable as fibres from animal products for blending wool. COSTS NOT DETERMINED. Because casein fibre has been produced in America only on an experimental basis, commercial costs have not been definitely determined. Gould and Whittier believe, however, that it can be manufactured to be sold at a price on a par with that of rayon. Although casein is dearer per pound than cellulose, agents used in treating casein fibres are cheaper than those used in making rayon. In addition, the chemical used in the casein process may be used over and over again, while that used for rayon manufacture cannot.

About 35 million .pounds of casein are produced in the United States annually, used principally as a paper coating and in the manufacture of plastics. Because of the almost unlimited supply of skim milk available in America it is possible to produce as much as one billion pounds of casein annually. The American experiments seem to imply yet another threat to the natural wool, a threat that is made more real because of the Americans’ thoroughness and propensities for new industries.