Invention Of Post-It® Note

The accidental discovery of a glue that wouldn't stick, coupled with a conscientious chorister who didn't want to damage his hymn book, led to the invention of the Post-it Note, which has since become an indispensable part of office life.

The post-it Note was invented in 1974 by Arthur Fry (USA), an employee of the 3M Corporation. Necessity is said to be the mother of invention, but in fact the Post-it Note fulfilled a need that most people weren't aware they had - and its invention developed from an earlier serendipitous discovery by a colleague of Fry's, research chemist Spencer Silver (USA). Silver hat been researching adhesives, but instead of coming up with a strong glue, he came up with the exact opposite. Silver's patent, filed on behalf of 3M in 1970, states that: "This invention relates to inherently tacky, elestomeric, solvent-dispersible, solvent-insoluble, acrylate copolymer and a process of preparing the copolymer" - in other words, a glue that didn't stick.

Significantly, this weak glue was reusable, and it did not leave a sticky residue when it was removed - paradoxically, its weakness was its strength, because it was so weak that it did not even damage paper fibres after being stuck to a page. Silver thought that there must be a practical use for his invention, and even proposed a noticeboard covered with the glue to which notes could be stuck. But it wasn't until 1974 that a use was found: Art Fry, a member of a church choir, used Silver's "unglue" to stop the page markers from falling out of his hymn book by coating the top edge of each marker with the glue. Fry said later: "I needed to bookmark that would stay put, yet could easily be removed without damaging my hymnal."

For some three years, Fry developed his idea to the point that it was marketable. At one point, he wrote a note to a colleague on one of his bookmarks, and it came back with the response written below it on the same marker, prompting 3M to test-market Post-it Notes in 1977 as temporary notes rather than as bookmarks. Officially launched in 1980, Post-it Notes are now a worldwide phenomenon, to the delight of Art Fry: "It is like having your children grow up and turn out to be happy and successful."

Source - The Book Of Invention by Ian Harrison.