Pressure-sensitive adhesive tape is so versatile because it can stick two surfaces – ideally flat ones – together without the need for heat, solvents or other substances in order to make it tacky. Instead, this amazing invention uses something as simple as a little pressure to make it stick fast.
Synthetic transparent cellulose acetate film (historically this was made of natural cellulose derived from plants like cotton or hemp) is made sticky through the addition of synthetic rubber resin, but how are these layers adhered together in the first place?
By first applying a primer to the side of the cellophane film that will host the adhesive, the manufacturers can then apply a very thin layer of the rubber-based glue. Next, by heating or applying hot air to the tape, any liquid present in the adhesive will evaporate, leaving behind a purer dose of glue.
Some other types of sticky tape involve laminating the glue to the tape using extreme pressure. The tape is then rolled onto a cardboard barrel for easy dispensing – often with the use of a clever device which keeps that elusive end of the tape accessible for the user.