Use of starch dispersions as binder in coating compositions and process for preparing the starch dispersions

• Main Authors: STOLLMAIER FRIEDERIKE THERESIA, ANNEN THOMAS MARTIN STEPHAN, HILLS MICHAEL ROBERT, HELBLING ANDRE MARCEL
• Format: Patent
• Language: English
• Published: 23.10.2007
• Subjects: ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; ADHESIVES; CHEMICAL PAINT OR INK REMOVERS; CHEMISTRY; COATING COMPOSITIONS, e.g. PAINTS, VARNISHES ORLACQUERS; COMPOSITIONS BASED THEREON; COMPOSITIONS OF MACROMOLECULAR COMPOUNDS; CORRECTING FLUIDS; DERIVATIVES THEREOF; DYES; FILLING PASTES; IMPREGNATING OR COATING OF PAPER; INKS; METALLURGY; MISCELLANEOUS APPLICATIONS OF MATERIALS; MISCELLANEOUS COMPOSITIONS; NATURAL RESINS; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ORGANIC MACROMOLECULAR COMPOUNDS; PAINTS; PAPER NOT OTHERWISE PROVIDED FOR; PAPER-MAKING; PASTES OR SOLIDS FOR COLOURING OR PRINTING; POLISHES; POLYSACCHARIDES; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; PRODUCTION OF CELLULOSE; PULP COMPOSITIONS; TEXTILES; THEIR PREPARATION OR CHEMICAL WORKING-UP; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; USE OF MATERIALS AS ADHESIVES; USE OF MATERIALS THEREFOR; WOODSTAINS

Coating compositions comprising a pigment and starch dispersion of discrete crosslinked starch particles in an aqueous liquid. The dispersion may be used as coating color for paper. A preferred process of preparing the dispersion of starch particles comprises (a) obtaining a mixture of starch and an aqueous liquid; (b) processing the mixture using shear forces in the presence of a crosslinker in an extruder; and (c) injecting a hydroxylic liquid into the extruder and dispersing the mixture inside the extruder or outside the extruder or both inside and outside the extruder to obtain the dispersion.