Methods for making multiple layer sheet materials
US5705111A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 20, 1995 |
| Grant date | Jan 6, 1998 |
| Priority date | — |
| Expiry date | Jan 20, 2015 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29C48/495
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
Methods related to coextrusion of heat-sensitive polymer materials. The sensitive melt stream element (12) is encapsulated in a second polymeric melt stream element (16). Transport means (36) is preferably employed between the encapsulating means (20) and the die (42). A third melt stream element (68) is joined to one or both opposing surfaces (70) of the second melt stream element (16) between the encapsulating means (20) and the die (42). In the die (42) the encapsulated melt stream element (12) becomes an interior layer (46) between encapsulating layers (48A, 48B) derived from the second melt stream element (16). The third melt stream element (68) forms layers (72, 74) positioned outwardly of the encapsulating layers (48A, 48B). The positioning, on the interior of the extrudate, of edges (54) of layer (46) is adjusted independently of the combined thicknesses of a layer derived from the third melt stream element (68) and an adjacent layer (48).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.