Filler Composition
Patent No. EP2362016 (titled "Filler Composition") was filed by Akzo Nobel on Jul 14, 2008. The application was issued on Nov 2, 2022.
Patent Summary
A filler composition for papermaking comprises: a) a filler ($\ge$1 wt% of total composition); b) a cationic organic polymer (weight average molecular weight 5,000–700,000; charge density 1–10 meq/g) at $\le$30 kg/ton of filler; c) an anionic polysaccharide with a net anionic group degree of substitution of 0.15–0.50; and d) a cationic inorganic compound (0–30 kg/ton of filler). The composition is used as an additive in aqueous cellulosic suspensions to produce paper via draining. Preparation involves mixing components, preferably adding cationic inorganic and organic compounds to the filler before adding the anionic polysaccharide. The resulting paper exhibits improved surface smoothness, printability, opacity, and brightness while mitigating strength loss.
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Date
Description
EP2362016
- Application Number
- EP11164265A
- Filing Date
- Jul 14, 2008
- Status
- Patent Maintained As Amended
- Sep 30, 2022
- Publication Date
- Nov 2, 2022
- External Links
- Slate, Register , Google Patents