Fatty acid ester of cellulose, cellulose diacetate and processes for the preparation thereof
US5977346A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 26, 1996 |
| Grant date | Nov 2, 1999 |
| Priority date | — |
| Expiry date | Nov 26, 2016 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08B3/06
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A fatty acid ester of cellulose having excellent transparency, filterability and spinnability in spite of its high content of mannose and xylose, wherein the total molar content of mannose and xylose accounts for at least 7% of that of glucose, mannose and xylose, and the amount of filtration satisfies a specified requirement. Such a fatty acid ester of cellulose is prepared by using a pulp having a low .alpha.-cellulose content as a raw material and a fatty acid corresponding to the ester as a diluent and adding an organic solvent in an amount of at least 10% by weight based on the diluent in any step during the preparation. In the preparation of cellulose diacetate, which excellent filterability and transparency, by the acetic acid process, the cellulose diacetate obtained by aging is dissolved in a solvent which can dissolve it and the resulting cellulose diacetate is recovered.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.