Post-it Notes began as a failed adhesive. Spencer Silver developed a repositionable acrylic adhesive in 1968 that nobody could use for twelve years. Art Fry applied it to choir bookmarks in 1980. A global product was born.
The Adhesive Patent
Key patent: US3,691,140 (Google Patents). The core invention was an adhesive that holds without permanently bonding and leaves no residue when removed.
Patent Thicket Strategy
3M surrounded the core adhesive patent with additional patents covering manufacturing, paper-adhesive combinations, and dispensers. This made imitation difficult even after the central patent expired.
Trademark Defense
As Post-it became synonymous with repositionable notes, 3M actively prevented genericization by promoting “Post-it Brand Notes” over “Post-its” in communications, monitoring media usage, and issuing usage guidelines.
After the Patents Expired
Competitors entered when patents lapsed. Many brands now sell repositionable pads. But Post-it retains dominant recognition built during years of exclusivity. The monopoly ended; the brand advantage persisted.
Invention vs. Application
Silver’s adhesive existed for 12 years before Fry found the right problem for it. Patents protected the commercialization moment, not the invention moment, giving 3M time to build a market. That is what patents most reliably do.
Sources
For informational purposes only. Not legal advice.
コメント