Process for the production of a coated substrate comprising cellulosic fibres

• Main Authors: Hillergren, Magnus, Ström, Göran, Aulin, Christian, Flodberg, Göran, Axrup, Lars, Lindström, Tom, Ljungqvist, Carl-Henrik
• Format: Patent
• Language: English
• Published: 22.12.2023
• Subjects: ACCESSORIES, CLOSURES, OR FITTINGS THEREFOR; CONTAINERS FOR STORAGE OR TRANSPORT OF ARTICLES OR MATERIALS,e.g. BAGS, BARRELS, BOTTLES, BOXES, CANS, CARTONS, CRATES,DRUMS, JARS, TANKS, HOPPERS, FORWARDING CONTAINERS; CONVEYING; HANDLING THIN OR FILAMENTARY MATERIAL; IMPREGNATING OR COATING OF PAPER; LAYERED PRODUCTS; LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT ORNON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM; PACKAGES; PACKAGING ELEMENTS; PACKING; PAPER NOT OTHERWISE PROVIDED FOR; PAPER-MAKING; PERFORMING OPERATIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; PRODUCTION OF CELLULOSE; PULP COMPOSITIONS; STORING; TEXTILES; TRANSPORTING; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G

The present invention relates to process for the production of a coated substrate comprising cellulosic fibres, the process comprising the steps of: i) providing a first substrate comprising cellulosic fibres and having a dry content of less than 50%; ii) applying a coating composition to the first substrate in an amount of more than 5 g/m2,,calculated as dry weight of the coating composition, wherein the coating composition comprises: - microfibrillated cellulose (MFC), and - optionally a water retention agent selected from carboxymethyl cellulose (CMC), anionic polyacrylamide (A-PAM),sodium polyacrylates, polyacrylic acid derivatives, guar gum, alginate, MFC prepared from carboxymethylated fibers, MFC prepared from oxidized fibers, MFC preparedby CMC- functionalised fibers, and/or combinations thereof; and iii) mechanically dewatering the first substrate. The present process provides an energy efficient coating process which can be performed online.