What was the original 'failed' adhesive that led to the invention of Post-it Notes called before it became a successful product?

In the world of office supplies, few inventions have had as much impact as the humble Post-it Note. This small adhesive paper has transformed how we organize information, communicate ideas, and remember important tasks. But behind this simple product lies a fascinating story of accidental discovery, persistence, and innovative product development. Test your knowledge about one of the most successful office products in history!

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Acrylate Copolymer #972
Spencer Silver's Microspheres
3M Compound #B-565
Acrylate Copolymer #400