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US 5,308,441 AGranted
Paper sizing method and product
AssigneeWestvaco Corporation
InventorNicholas T. Kern
Life of this patent
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AssigneeWestvaco Corporation
InventorNicholas T. Kern
Estimating the term…
Paper that is uniquely suitable for use in the aseptic packaging of foods, beverages, and the like is produced via a two step sizing process comprising an internal size step and a surface size step. The internal size includes approximately 1.0% anionic rosin and about 1.3 to 2.6% alum (based on the dry pulp weight) blended to a 4.0 to 4.5 pH controlled papermachine headbox stock furnish. Following web formation and drying, the surface size is applied with a composition including about 0.025 to 0.050% alkyl ketene dimer (based on the dry pulp weight) blended with a traditional starch formulation and sufficient sodium bicarbonate to both neutralize any unreacted alum present near the surface of the internally sized web and to produce a paper having a water extractable pH level of from about 4.0 to below 6.0. Secondary web drying follows the surface size application.
A paper sizing process comprising the steps of:
A paper comprising cellulosic fibers internally sized with about 1.0% of the dry fiber weight being an anionic rosin and about 1.3 to 2.6% of the dry fiber weight being alum, said internally sized paper being surface sized on at least one side thereof with a sizing blend comprising about 0.025 to 0.050% by dry fiber weight of a synthetic sizing compound and about 0.125 to 0.150% by dry fiber weight of sodium bicarbonate, said surface sizing substantially neutralizing any unreacted alum present near a surface of said internally sized paper and producing paper having a water extractable pH level of from about 4.0 to below 6.0.
A paper comprising cellulosic fiber produced by the process of:
Dependencies are inferred from the claim text.