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Filler For Papermaking Process

Patent No. EP1704282 (titled "Filler For Papermaking Process") was filed by Akzo Nobel on Dec 20, 2004. The application was issued on Aug 30, 2023.

Patent Summary

This filler comprises a calcium salt and an amphoteric cellulose derivative containing both cationic and anionic groups. The cellulose derivative is characterized by a net anionic substitution, where anionic groups are in net excess. Specifically, the degree of anionic substitution ($\text{DS}_A$) ranges from 0.01 to 1.0, and the degree of substitution of net anionic groups ($\text{DS}_{NA}$) ranges from 0.01 to 0.60, defined as the average number of anionic groups minus the average number of cationic groups per glucose unit. The filler is produced by mixing a calcium salt-containing material with the cellulose derivative and is used as an additive in papermaking processes to improve sizing efficiency, drainage, retention, and paper properties.

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CompanyOpposition DateRepresentative
AECHTERJan 25, 2019TER MEER STEINMEISTER & PARTNER

Dossier Documents

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  • Date

    Description

EP1704282

AKZO NOBEL
Application Number
EP04809143A
Filing Date
Dec 20, 2004
Status
Patent Maintained As Amended
Jul 28, 2023
Publication Date
Aug 30, 2023
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