Preparation of composite fibers and diaphragms

US6352660B1 · kind B1 · utility

Assignee

• BASF SE

Inventors

• Holger Friedrich · Frankenthal (Pfalz), DE
• Ulrich Bröckel · Freinsheim, DE
• Dieter Schlafer · Ludwigshafen, DE
• Klaus-Dieter Hoppe · Monsheim, DE
• Kurt Hecky · Zeiskam, DE
• Peter Palm · Gerolsheim, DE

Key dates

• Filing date: Oct 21, 1998
• Grant date: Mar 5, 2002
• Expiry date: Oct 21, 2018

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T428/31544
• WIPO field: Textile and paper machines
• WIPO sector: Mechanical engineering

Abstract

Composite fibers useful for preparing diaphragms are prepared by(a) mixing a PTFE or PTFE copolymer dispersion or powder with a finely divided inorganic material and a fiber forming material,(b) shear heating the resulting mixture to a temperature at which sheared to PTFE or PTFE copolymer becomes flowable without showing signs of decomposition while removing the dispersion medium, if a PTFE or PTFE copolymer dispersion is used,(c) cooling the mixture to below 70° C.,(d) mix shearing the mixture at below 70° C. to form composite fibers.