Rubber is familiar under a sneaker, but its use in footwear has a longer history than any one modern style. The material and its processing opened up manufacturing options; they did not make every earlier shoe rigid or every rubber sole equally grippy.
What is vulcanization?
The Smithsonian’s account of a vulcanized rubber object explains that Charles Goodyear discovered a process in 1839 involving heat and sulfur. The museum contrasts the behavior of untreated natural rubber in heat and cold with vulcanized rubber’s properties. The story of rubber use itself is broader and older than this one development.
From material to shoe
Vulcanized rubber could be used in many products, including footwear. The Smithsonian describes a Vans outsole mold and a production process in which rubber outsoles are heated and placed on a lasted upper before curing is complete. This is a specific later example of shoe manufacturing, not the first rubber-soled shoe.
Different factories and products use different methods. The industrial shoemaking guide explores the parallel development of machines and factory work.
Rubber, leather and other soles
Rubber outsoles can be made in different compounds and tread patterns. Leather soles also vary by construction and finish. Neither material guarantees traction on wet tile, ice or every other surface. Compare the specific outsole and use it with care in unfamiliar conditions.
Thickness does not necessarily mean softness, and the outsole is only one layer of a shoe. Our sole and midsole guide explains how the layers differ.
What about environmental claims?
A material may contain natural, recycled or bio-based ingredients, but these terms do not establish the impact of an entire pair. Look for the percentage, component and supporting evidence. Our material claims guide offers questions to ask.
Frequently asked questions
Did vulcanization invent rubber? No. Vulcanization is a process applied to rubber; rubber itself was already known and used.
Are all rubber soles waterproof? A sole’s material does not make the whole shoe waterproof. Water can enter through seams or the opening.
Do rubber soles always grip better? Grip depends on compound, tread, wear and the surface. No sole is reliable on every surface.
For the components around the outsole, see our shoe anatomy guide.
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