Preparation and use of iminodisuccinic acid salts
AssigneeBayer Aktiengesellschaft
InventorsTorsten Groth, Winfried Joentgen, Paul Wagner, Frank Döbert, Eckhard Wenderoth, Thomas Roick
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Abstract
A process for the preparation of iminodisuccinic acid alkali metal salts by reaction of maleic acid and ammonia in an aqueous medium in the presence of alkali metal hydroxides and working up thereof.
Claims3
In a papermaking process comprising the step of processing a thermomechanical pulp comprising fibers, the improvement comprising adding to the pulp, iminodisuccinic acid alkali metal salts for bleaching the pulp, wherein addition of the iminodisuccinic acid alkali metal salts to the pulp increases the degree of whiteness and brightness of plant fibers utilized in the papermaking process.
Dependencies are inferred from the claim text.