"Curls last until you cut them off." Apparently if users of this product were dissatisfied with the results they'd have to shave their heads.
These days you'd have to go to a hardware store to purchase what women were putting on their hair in the 1950s. Weatherproof silicone coating? Today it's sold as Thompson's® WaterSeal® and used for waterproofing wood and concrete. At any rate, silicone coatings for "weatherproofing" hair were soon overshadowed among hair care products by the far superior epoxy resin coatings which enabled hair to withstand Category Five hurricanes.