The 2-15-96 NYT reports on the design and manufacture of the new high-tech Swiss bank note: The 50-franc bill is the world's first digital bank note -- designed on a computer that resolves its design into 2.5 billion points, each of them individually accessible electronically. There are more than 20 security features, though the precise number is a secret. Its design is vertical rather than horizontal. Ten printing processes are involved, including silk screening for the chameleon numbers and hot stamping for the silvery elements. The Swiss say American bills are "a little outdated, even the new ones, as far as the state of the art goes." 2.5_bil