Anionic preflocculation of fillers used in papermaking
AssigneeEcolab USA Inc.
InventorsWeiguo Cheng, Katherine M Broadus, Dorota Smoron, Shawnee M Wilson
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Abstract
A method of preparing a stable dispersion of flocculated filler particles for use in papermaking processes comprises use of an anionic first flocculating agent to an aqueous dispersion of filler particles, followed by addition of a second anionic flocculating agent to the dispersion and further optional shearing of the resultant filler flocs to the desired particle size resulting in shear resistant filler flocs with a defined and controllable size distribution.
Claims13
A method of preparing a stable dispersion of flocculated filler particles having a specific particle size distribution for use in papermaking processes comprising:
- a) adding a first flocculating agent to an aqueous dispersion of filler particles, the dispersion in an amount sufficient to mix uniformly in the dispersion without causing significant flocculation of the filler particles the first flocculating agent being anionic and having an RSV of at least 3 dL/g;
- b) adding a second flocculating agent to the dispersion in an amount sufficient to initiate flocculation of the filler particles in the presence of the first flocculating agent wherein the second flocculating agent is anionic;
- c) shearing the flocculated dispersion to provide a dispersion of filler flocs having the desired particle size;
- and
- d) causing or allowing flocculation of the filler particles prior to adding them to a paper stock and wherein no paper stock is present during the flocculation.
Dependencies are inferred from the claim text.