US 12,215,463 B2
Process for producing paper or board and a product thereof
Diego Salas, Madrid (ES); Jinho Lee, Seoul (KR); and Jan-Luiken Hemmes, Bergisch Gladbach (DE)
Assigned to Kemira Oyj, Helsinki (FI)
Appl. No. 17/414,387
Filed by KEMIRA OYJ, Helsinki (FI)
PCT Filed May 22, 2019, PCT No. PCT/FI2019/050396
§ 371(c)(1), (2) Date Jun. 16, 2021,
PCT Pub. No. WO2020/128144, PCT Pub. Date Jun. 25, 2020.
Claims priority of application No. 20186091 (FI), filed on Dec. 17, 2018.
Prior Publication US 2022/0090319 A1, Mar. 24, 2022
Int. Cl. D21H 11/18 (2006.01); D21F 1/00 (2006.01); D21H 17/26 (2006.01); D21H 17/29 (2006.01); D21H 17/55 (2006.01); D21H 17/56 (2006.01); D21H 21/20 (2006.01); D21H 23/04 (2006.01); D21J 1/00 (2006.01)
CPC D21F 1/0018 (2013.01) [D21H 11/18 (2013.01); D21H 17/26 (2013.01); D21H 17/29 (2013.01); D21H 17/55 (2013.01); D21H 17/56 (2013.01); D21H 21/20 (2013.01); D21H 23/04 (2013.01); D21J 1/00 (2013.01)] 19 Claims
OG exemplary drawing
 
1. A process for producing paper or board, comprising:
slushing a stock of dried fibres in a slushing system comprising a pulper, and/or feeding a stock of never-dried fibres in a fibre line of an integrated paper mill;
adding a polymeric strength additive comprising at least one polysaccharide to one or more of the stocks of dried fibres and never-dried fibres into the pulper or to the fibre line;
deflaking and/or refining the stock in a deflaker and/or a refiner;
directing a deflaked and/or refined stock from the deflaker and/or refiner into a mixing chest and from the mixing chest to a machine chest;
obtaining a thin stock by diluting the deflaked and/or refined stock with white water from a white water silo;
directing the the thin stock to a headbox;
forming a web; and
drying the web;
wherein the polymeric strength additive has an intrinsic viscosity of at least 200 ml/g, and
wherein consistency of the stock in the slushing system and/or in the fibre lines is 4-20 wt. % at the time and point of the addition of the polymeric strength additive.