US 12,252,593 B2
Process for preparing a lignin-based resin
Ben Nasli Bakir, Saltsjö-boo (SE); and Dimitri Areskogh, Stockholm (SE)
Assigned to Stora Enso OYJ, Helsinki (FI)
Filed by Stora Enso OYJ, Helsinki (FI)
Filed on Dec. 13, 2021, as Appl. No. 17/643,970.
Application 17/643,970 is a division of application No. 16/604,462, abandoned, previously published as PCT/IB2018/052536, filed on Apr. 11, 2018.
Claims priority of application No. 1750438-2 (SE), filed on Apr. 12, 2017.
Prior Publication US 2022/0106446 A1, Apr. 7, 2022
This patent is subject to a terminal disclaimer.
Int. Cl. C08J 3/03 (2006.01); B27N 3/00 (2006.01); C08L 97/00 (2006.01)
CPC C08J 3/03 (2013.01) [B27N 3/002 (2013.01); C08L 97/005 (2013.01); C08J 2397/00 (2013.01); C08J 2461/06 (2013.01)] 21 Claims
 
1. A method for preparing a resin comprising the steps of
a) providing an aqueous medium having a pH of 6;
b) adding lignin to the aqueous medium;
c) mixing until a dispersion of lignin in the aqueous medium has been obtained;
d) adding alkali, phenol and formaldehyde to the dispersion to form a mixture; and
e) maintaining the mixture at a temperature of from 30° C. to 95° C. for at least 30 minutes.