Currency: The Polyester Greenback

The U.S. Treasury has fretted for years about a generation of office copiers now being developed that will reproduce colors much more accurately than current models do. These new machines, officials believe, could lead to widespread counterfeiting, even by amateur crooks. As a result, the Treasury said last week, the U.S. greenback is undergoing its first major design change since 1929.

Beginning in about twelve months, new U.S. paper currency will contain a thin polyester stripe bearing the legend USA ONE for $1 bills, USA FIVE for $5 bills, and so on. Called a security thread, the stripe is transparent and will not reflect light. Thus it cannot be reproduced by a photocopier. Around the portraits on the new bills will be letters too tiny for copy machines to pick up that say UNITED STATES OF AMERICA.