… In the 1950s, Procter & Gamble had developed a ground-breaking and revolutionary toothpaste formulation (the first ever ‘fluoride’ toothpaste) to combat tooth decay but were hamstrung in its launch (which P&G christened as fluoristan) that was very aggressive and corrosive. The standard packaging system for toothpaste at that time was the collapsible aluminum tube that was produced by impact extrusion of aluminum slugs.
Collapsibility was essential as air or moisture could not be allowed to enter the tube after the toothpaste was dispensed. Direct contact with stannous fluoride was a serious problem because it caused metals to corrode. Even when inside of the metal tube was coated with the most resistive lacquers known at that point in time, it penetrated the lacquers and incidence of corrosion was unacceptably high…
*Read the full article online at https://packagingsouthasia.com/polymers/the-chemical-resistance-and-direct-contact-properties-of-polymers/