Lignin dispersing agents and method of making same
Abstract
Abstract This invention relates to the production of dispersing agents from mixtures of spent sulphite liquor solids and Kraft liquor solids. Although appropriate physical mixtures of said solids without further treatment have useful dispersant characteristics for specific applications, the preferred way of preparing improved dispersant compositions from mixtures of said solids consists in heat treating concentrated aqueous solutions thereof for 1 to 3 hours at 100* to 160*C, at pH values higher than 11.0. The heat treatment is preferably performed under simultaneous blowing of air through the reaction mixture. The addition of a crosslinking agent, such as formaldehyde, is optional in cases where the air blowing treatment is not employed during the heat treatment. The dispersing agents of this invention have utility as dye dispersants, carbon black dispersants, clay dispersants, and the like.
Inventors
- 👤 Julius Benko
- 👤 Gilles Daneault
Bibliographic Details
Claims Analysis
Total Claims: 7References Cited (Backward Citations)
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| 3.5 Years (Year 4) | 1978-02-03 | 1978-08-05 | 1979-02-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-02-03 | 1982-08-05 | 1983-02-04 | $3760.00 | Window Closed / Lapsed |
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