The sole formation process
In the single-layer molding technology, foamed polyurethane (PU) is used — initially a thermosetting liquid polymer capable of curing into a solid under the influence of high temperatures. As it expands, it fills the upper part of the mold. The shoe upper, stretched over a last, is lowered into the mold. Then PU is injected into the mold, and the sole is formed in the molding unit.
The result is footwear with a single-layer PU sole. Footwear with a polyurethane sole is lightweight, oil- and petrol-resistant (MBS), and resistant to acids and alkalis. Suitable for use in a temperature range from -10ºC to +50ºC.
Various types of molding units are used at the Vostok-Service Group's facilities to produce single-layer soles, including equipment from DESMA (Germany), equipped with specialized programs that enable control of the resulting sole's density, monitoring of the product weight, and control of the chemical process cycles.
Our shoemakers' arsenal includes high-tech auxiliary equipment — robots for roughening and spraying release agents, and equipment for dye injection.