Mould for taking cast from foot tread surface - by pressing foot in plastic particles surrounded by flexible film

摘要

Appts. for taking a cast from a foot tread surface, for mfr. of orthopaedic footwear, linings and shoe trees, operates by pressing the foot in particles at least partly surrounded by a flexible elastic film, pumping out the air between the particles, fixing the particles relative to each other by the air pressure, then filling the cast with a rapid-solidifying moulding material. The particles have good free-flowing properties and comprise a mixt. of particles of greatly varying size or equal size. They may consist of thermoplastic material e.g. polyethylene or polypropylene ground for regeneration or plastic or synthetic resin beads suitable for ion exchangers with a bulk density of approx. 200-400g-l.