| 摘要 |
Paper or paperboard is made by forming an aqueous cellulosic suspension, passing the cellulosic suspension through one or more shear stages, draining the suspension to form a sheet and drying the sheet, wherein the cellulosic suspension that is drained includes organic polymeric material and inorganic material, wherein said organic polymeric material is a flocculant having a molecular weight above 500,000 and is added to the suspension before one of the said shear stages and wherein said inorganic material comprises bentonite which added to the suspension after that shear stage, characterised in that the organic polymeric material comprises an anionic or non-ionic polymer.
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