Composite semipermeable membrane, process of producing the same and method of producing highly pure water using the same
US5178766A · kind A · utility
41Cited by
6References
10Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Aug 8, 1991 |
| Grant date | Jan 12, 1993 |
| Priority date | — |
| Expiry date | Aug 8, 2011 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S210/90
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A composite semipermeable membrane which has a high electrolytes rejection even when the concentration of the electrolytes in feed water is very low and even if the pH of feed water is not less than 8 is disclosed. The composite semipermeable membrane of the present invention comprises a microporous substrate and a cross-linked polyamide-based ultra-thin membrane laminated on the microporous substrate, the ultra-thin membrane having a covalently bonded quaternary nitrogen atom.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.