Process for production of paper
AssigneeKemira Oyj
InventorsAri Juppo, Ulf Stenbacka
Life of this patent
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Abstract
The invention relates to a process for the production of paper or board comprising: adding a retention system to a stream of stock entering a paper machine head box, directing the stream of stock to a wire, de watering the stream of stock on the wire to form a paper web, and drying the paper web, wherein the retention system comprises a water-soluble cationic polymer, and nanocellulose acting like a micro particle, wherein the nanocellulose is added in an amount of less than 1% as active substance based on dry solids weight of the stock.
Claims25
A process for the production of paper or board comprising:
- adding components of a retention system comprising a water-soluble cationic polymer and nanocellulose acting like a microparticle, sequentially to a stream of stock entering a paper machine headbox,
- directing the stream of stock to a wire,
- dewatering the stream of stock on the wire to form a paper web, and
- drying the paper web,
- wherein the water-soluble cationic polymer is added to form flocs followed by subjecting the stock to shearing forces to break up the flocs and then adding the nanocellulose, and wherein the nanocellulose is added in an amount of less than 1% as active substance based on dry solids weight of the stock.
Use of nanocellulose as a material acting like a microparticle for improving the retention of papermaking raw materials during the production of paper or board, wherein the nanocellulose is used together with a retention aid comprising a water-soluble cationic polymer in such as manner that the nanocellulose is added after the water-soluble cationic polymer, and wherein the nanocellulose is used in an amount of less than 1% as active substance based on dry solids weight of the papermaking stock.
Dependencies are inferred from the claim text.