Production of cellulose acetate
US4162359A · kind A · utility
6Cited by
3References
7Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Mar 13, 1978 |
| Grant date | Jul 24, 1979 |
| Priority date | — |
| Expiry date | Mar 13, 1998 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08B3/06
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
Cellulose acetate is produced by subjecting highly purified cellulosic dissolving pulp to a bleaching sequence including at least one alkaline extraction stage and acetylating the bleached pulp to convert the pulp to cellulose acetate. The yellowness index of the cellulose acetate is reduced by carrying out the alkaline extraction stage in the presence of from 0.2 to 3.3%, based on dry pulp weight, of sodium or hydrogen peroxide.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.