adhesive patentSometimes an inventor will make a best selling product completely be accident. The Post It Note is an example of that. In 1968, Dr. Spencer Silver invented a repositionable adhesive that was strong enough to stick to surfaces but did not leave any residue. Silver had not set out to produce such a glue. He was actually trying to make a very strong adhesive. Patent Number #3691140 for Acrylate Copolymer Microspheres, the adhesive used on Post It Notes was granted to Spencer Ferguson Silver on March 9, 1970. But 3M never utilized this adhesive. Continue reading “Invention of Post It Notes – An Accidental Discovery With a Sticky Past”