Higher purity imidazoline based amphoacetate surfactants and processes for the preparation thereof
US5744063A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 18, 1997 |
| Grant date | Apr 28, 1998 |
| Priority date | — |
| Expiry date | Feb 18, 2017 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S516/915
- WIPO fieldPharmaceuticals
- WIPO sectorChemistry
Abstract
Imadazoline-based amphoacetates of higher purity, containing essentially negligible amounts of unalkylated amido amines, lower amounts of glycolic acid salts and monochloroacetate salts, superior to currently available conventional amphoacetates, are provided. This is demonstrated by their improved surface-active properties. Lower inherent irritation properties may be expected due to improved purity. The higher purity amphoacetates can be obtained via processes utilizing precise pH control during the reaction of imidazoline, or its open-chain derivatives, with alkylating agents, e.g. sodium monochloroacetate. The pH can be controlled by adding the base slowly or automatically in response to a pH metering device to maintain a constant pH, or by a series of staged additions which are calculated to maintain pH within a stated range. The reaction may also be carried out by conducting the initial hydrolysis of the imidazoline ring structure, followed by alkylation. These higher-purity amphoacetates contain essentially fully alkylated products and lower amounts of glycolic acid derivatives, even though a ratio of SMCA to substituted imidazoline, or its open-ring derivative, of less than …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.