Patent · US Expired

Method for preparing a uniform polyolefinic microporous hollow fiber

US4541981A · kind A · utility

31Cited by
4References
5Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 13, 1983
Grant dateSep 17, 1985
Priority date
Expiry dateJun 13, 2003

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB01D69/08
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

The present invention provides microporous hollow fiber with improved structural and performance characteristics and a process and apparatus for preparing the improved fiber. The microporous hollow fiber possesses substantially uniform wall thickness, cross-sectional dimensions and porosity. Such characteristics are obtained by melt spinning hollow fiber precursor under defined conditions in a substantially vertically upward direction and subjecting the precursor to a symmetrical quenching step which may be achieved using a hollow annular structure surrounding the precursor. The structure, which is connected to a source of gas, has one or more openings on its inner surface that distribute the gas against the precursor in a substantially uniform manner.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.