Process for producing orthopedic structures and a thermoplastic linear polyurethane for use in such process
US4316457A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 9, 1980 |
| Grant date | Feb 23, 1982 |
| Priority date | — |
| Expiry date | Oct 9, 2000 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S602/90
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A process for producing a rigid orthopedic cast in which a bandage material is provided which is impregnated or coated in the form of webs or sheets with a solvent solution of a polyurethane prepolymer, a bifunctional chain-extender and a catalyst. The prepolymer urethane having two isocyanate end groups, being formed by the reaction of a bifunctional compound reactive with an isocyanate group with a molar excess of a diisocyanate, forms a final thermoplastic polymer in the presence of the chain-extender when the solvent is removed under evaporative conditions. The heated thermoplastic impregnated fabric can be wrapped in multiple layers under normal conditions around a broken body member, molded and cooled to form a strong, rigid supportive cast which is porous so as to prevent skin maceration or other medical ramifications related to a non-porous material.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.