Polystyrene foam extrusion
US4098941A · kind A · utility
22Cited by
7References
4Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Dec 8, 1976 |
| Grant date | Jul 4, 1978 |
| Priority date | — |
| Expiry date | Dec 8, 1996 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/249961
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
Polystyrene foam is extruded upwardly as a tube into a cooling media of boiling water, both the interior and exterior surfaces of the cylindrically shaped extrudate passing through a bath of boiling water of variable depth. The polystyrene foam extrudate produced by such a method has a high density at the interior and exterior surfaces, with the density progressively decreasing from these surfaces toward the center core of the extrudate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.