Patent · US Expired

Process for continuous filtration and aging of xanthated alkali cellulose

US4289875A · kind A · utility

1Cited by
11References
13Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 29, 1979
Grant dateSep 15, 1981
Priority date
Expiry dateOct 29, 1999

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC08B9/04
  • WIPO fieldMacromolecular chemistry, polymers
  • WIPO sectorChemistry

Abstract

A process for the continuous filtration and aging of a viscose solution comprising xanthated alkali cellulose (XAC) is described wherein the XAC is continuously passed in a downstream direction through a series of aging tanks and a series of filter means. The aging tanks are so designed and arranged that the viscose solution is never partitioned into batches, as necessitated by common manufacturing systems, but constitutes a continuous, uninterrupted stream throughout aging filtration, deaeration and spinning. The filter means, standard plate and frame filters, are designed and installed in such a manner that the number of filter changes, or redressings, are substantially reduced in the aggregate, without increasing the number of filters now used in a standard plant, or sacrificing viscose quality. This results in less process interruption, loss of product, and less potential environmental pollution.

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