Aromatic polyimide composite separating membrane
US4528004A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 30, 1984 |
| Grant date | Jul 9, 1985 |
| Priority date | — |
| Expiry date | Jan 30, 2004 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31721
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
An aromatic polyimide composite membrane having a satisfactory gas-permeating property and an excellent gas-separating property comprises an aromatic polyimide porous membrane substrate and at least one coating layer which has been prepared (A) by coating at least one surface of the substrate with a dilute dope solution containing 0.01 to 5 parts by weight of a soluble aromatic polyimide and/or polyamic acid dissolved in a solvent which consists essentially of 100 parts by weight of a base component incapable of dissolving therein the substrate in an amount of 3% by weight or more and 0 to 15 parts by weight of an additional component capable of dissolving therein the 5% by weight or more of the aromatic polymeric material and compatible with the base component; and (B) by gradually evaporating the solvent from the coated dilute dope solution layer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.