Process for production of expanded polytetrafluoroetylene products
US7691299B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 1, 2003 |
| Grant date | Apr 6, 2010 |
| Priority date | — |
| Expiry date | May 1, 2023 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29L2031/7542
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
Disclosed are expanded polytetrafluoroethylene products, such as porous polytetrafluoroethylene tubes, having high axial tear strength and a process for their production. Each expanded polytetrafluoroethylene product has a microstructure, which comprises fibrils and nodes interconnected with each other by the fibrils, and has an axial tear strength of not lower than 6,000 gf/mm as calculated in accordance with the following formula: L/[T×(V/100)] where L (gf) is an axial tear load, T (mm) is a wall thickness, and V (%) is a volume ratio of resin. The process for the production of the expanded polytetrafluoroethylene product includes a high-speed extrusion step.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.