Process for the production of paper containing starch fibers and the paper produced thereby
AssigneeNational Starch and Chemical Corporation
InventorsHenry R. Hernandez, Donald S. Greif, Albert N. Barna, Douglas S. Thornton
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Abstract
A process for the production of paper and paperboard is disclosed wherein water-insensitive starch fibers, produced by extrusion of a starch dispersion into a coagulating solution, are employed to replace all or part of the cellulosic or other pulp conventionally employed. There is also disclosed a method for the incorporation of functional additives into paper during the production thereof; and a method for binding fibers in non-woven webs.
Claims18
In a process for manufacturing paper and paperboard comprising the steps of introducing an aqueous slurry of a fibrous pulp material onto a screen in such a manner that the water is removed thereby forming a sheet of consolidated fibers which, upon pressing and drying, yields the final paper product, the improvement comprising the step of replacing from 1 to 100% by weight of said pulp material with water-insensitive starch fibers of 10 to 500 microns in diameter, said fibers being produced by extruding a thread-like stream of a colloidal dispersion containing starch at 5-40% by weight solids, wherein said starch is present in an amount more than 50% by weight of the fiber forming ingredient, into a moving coagulating bath comprising an aqueous solution of a coagulating salt selected from the group consisting of ammonium sulfate, ammonium sulfamate, mono-basic ammonium phosphate, di-basic ammonium phosphate and mixtures thereof, the solution containing the coagulating salt in an amount at least sufficient to coagulate the starch, said starch fibers further characterized in retaining fiber integrity when dispersed in an aqueous medium.
A process for incorporating water-insoluble additives within an aqueous papermaking slurry of a conventional papermaking system comprising the steps of thoroughly dispersing at least one water-insoluble additive in a colloidal dispersion containing starch at 5-40% by weight solids, wherein said starch is present in an amount more than 50% by weight of the fiber forming ingredient, and precipitating said dispersion by extruding a thread-like stream of the dispersion into a moving coagulating bath comprising an aqueous solution of a coagulating salt selected from the group consisting of ammonium sulfate, ammonium sulfamate, mono-basic ammonium phosphate, dibasic ammonium phosphate and mixtures thereof, the solution containing the coagulating salt in an amount at least sufficient to coagulate the starch so as to form water-insensitive starch fibers encapsulating said additive;
- and subsequently using the resulting starch fibers as a component in a papermaking pulp system, said starch fibers further characterized in retaining fiber integrity when dispersed in an aqueous medium.
Dependencies are inferred from the claim text.