Spencer Ferguson Silver is an American chemist who, together with Arthur Fry, invented Post-it notes in 1970. Silver was born in San Antonio, Texas. He majored in chemistry at Arizona State University, earning a B.S. in 1962, then earned a doctorate in organic chemistry from the University of Colorado in 1966, before taking a position as a Senior Chemist in 3M's Central Research Labs. Silver is now named on over 20 US patents; but his most significant invention was not an immediate success. In 1968, Silver developed a high-quality but "low-tack" adhesive, made of tiny, indestructible acrylic spheres that would stick only where they were tangent to a given surface, rather than flat up against it. Spencer used the patented formula from Shiro Takemoto. As a result, the adhesive's grip was strong enough to hold papers together, but weak enough to allow the papers to be pulled apart again without being torn. More importantly, the adhesive could be used again and again. Silver wanted to market the adhesive as a spray, or as a surface for bulletin boards on which temporary notices could be easily posted and then removed. 

January 1st, 1941 in   /  Died:   May 8th, 2021