Process for making paper

Abstract

The invention relates to a process for making paper wherein an anionic starch, which is based on a starch comprising at least 95 wt. %, based on dry substance of the starch, of amylopectin, or a derivative of said starch, is used in combination with a fixative as a strengthening agent.

1 . A process for making paper wherein an anionic starch, which is based on a starch comprising at least 95 wt. %, based on dry substance of the starch, of amylopectin, or a derivative of said starch, is used in combination with a fixative as a strengthening agent.  
     
     
         2 . A process according to  claim 1 , wherein the starch is a root or tuber starch.  
     
     
         3 . A process according to  claim 2 , wherein the starch is a potato or tapioca starch.  
     
     
         4 . A process according to any one of claims  1 - 3 , wherein the derivative of the starch is obtained by an etherification or esterification reaction, or a combination thereof.  
     
     
         5 . A process according to any one of the preceding claims, wherein the fixative is a cationic compound having a charge density of at least 1 μeq/mg.  
     
     
         6 . A process according to any one of the preceding claims, wherein the fixative is chosen from the group of polyaluminum compounds, alum, cationic starch or a derivative thereof, polydimethyldiallylammonium chlorides, polyamines, polyvinylamines, polyethylene imines, and dicyandiamide polycondensates.  
     
     
         7 . Paper obtainable by a process according to any one of the preceding claims.  
     
     
         8 . The use of an anionic starch, which is based on a starch comprising at least 95 wt. %, based on dry substance of the starch, of amylopectin, or a derivative of said starch, as a strengthening agent in paper.  
     
     
         9 . The use of an anionic starch, which is based on a starch comprising at least 95 wt. %, based on dry substance of the starch, of amylopectin, or a derivative of said starch, for reducing the amount of a fixative in a process for making paper wherein an anionic starch is used as a strengthening agent.