Post-it note
Spencer Silver & Art Fry / 3M
The Post-it note is a small sheet of paper with a low-tack, reusable, pressure-sensitive adhesive. It emerged from a failed adhesive experiment (1968), five years of internal neglect, a hymn-book insight (1974), bootleg development, and opportunistic colour selection. Its communicative function was proven through employee message exchange—not market testing. The 1977 'Press 'n Peel' test failed; the 1978 Boise Blitz succeeded only after renaming and free-sample distribution. It is worth attention because it reveals how industrial innovation depends less on intention than on permission, accident, and low-fidelity validation.