Use of polyvinylamine to improve oil and water sizing in cellulosic products

Abstract

The presence of both a water sizing agent and an oil sizing agent in a paper making furnish is detrimental in that each has an adverse effect on the sizing property of the other. It has now been found that this adverse effect can be counteracted or lessened by the presence in the furnish of a polyvinylamine.

1 . In a paper making process in which a furnish is used, which furnish contains both an oil sizing agent and a water sizing agent as a part of the materials in the furnish, the improvement in which the furnish also contains a polyvinylamine.  
     
     
         2 . The process of  claim 1  in which the oil sizing agent is present in the furnish in an amount of between 0.005% and 1% active treatment solids based upon total furnish solids; the water sizing agent is present in an amount of between 0.005% and 1% active treatment solids based upon total furnish solids; and the polyvinlamine is present in an amount of between 0.001% and 1% active treatment solids based upon total furnish solids.  
     
     
         3 . The process of  claim 1  in which the oil sizing agent is a fluorocarbon containing polymer, and the water sizing agent is an alkyl ketene dimer.  
     
     
         4 . The process of  claim 2  in which the oil sizing agent is a fluorocarbon containing polymer, and the water sizing agent is an alkyl ketene dimer.  
     
     
         5 . The process of  claim 2  wherein the polyvinylamine has a hydrolysis level of at least 35%.  
     
     
         6 . The process of  claim 1  in which the order of addition to the furnish of oil sizing agent, water sizing agent and polyvinylamine, is adding the water sizing agent, then adding the polyvinylamine either before or after the water sizing agent followed by adding the oil sizing agent.  
     
     
         7 . The process of  claim 3  in which the order of addition of fluorocarbon containing polymer, the alkyl ketene dimer and the polyvinylamine, is adding the alkyl ketene dimer, adding the polyvinylamine either before or after adding the alkyl ketene dimer, followed by adding the fluorocarbon containing polymer.  
     
     
         8 . A paper furnish that contains an oil sizing agent, a water sizing agent, and a polyvinylamine.