Multi-function starch compositions

Abstract

The invention relates to a dry mix composition comprising a starch component and a papermaking additive, particularly an uncooked starch component and a heat sensitive papermaking additive. The dry mix can be added to water to form a slurry. The invention further concerns the application of the slurry to a paper mat in paper manufacturing and a process for making the dry mix composition.

1 . A method of applying heat sensitive papermaking additives to paper during a papermaking process comprising the steps of 
 a) providing a dry mix comprising an uncooked starch component and one or more heat sensitive papermaking additives;    b) adding the dry mix to water to form a slurry without cooking the starch;    c) providing a paper mat having a top surface and a bottom surface;    d) applying the slurry to the top surface of the paper mat and allowing at least some of the slurry to permeate to the bottom surface of the paper mat; and    e) heating the paper mat after applying the slurry to cook some or all of the starch.    
   
   
       2 . The method of  claim 1  wherein the slurry comprises the uncooked starch component in an amount of from about 0.1% to about 20%, by weight, and about 0.01% to about 10%, by weight of the uncooked starch component, of the heat sensitive papermaking additives.  
   
   
       3 . The method of  claim 1  wherein the heat sensitive papermaking additives are selected from the group consisting of optical brightening agents, fluorescent agents, dry strength agents, filler particles, sizing agents, flame retardants, pigments and combinations thereof.  
   
   
       4 . The method of  claim 1  wherein the uncooked starch component is selected from the group consisting of unmodified starch, modified starch, dextrin, maltodextrin and combinations thereof.  
   
   
       5 . The method of  claim 4  wherein the unmodified starch or modified starch are derived from a source selected from the group consisting of corn, wheat, barley, tapioca, rice, potato and combinations thereof.  
   
   
       6 . The method of  claim 4  wherein the unmodified starch or modified starch is pearl starch.  
   
   
       7 . The method of  claim 1  wherein the slurry is applied to the paper mat by spraying the slurry onto the top surface of the paper mat with a spray bar.  
   
   
       8 . The method of  claim 1  wherein the slurry is applied to the paper mat by spraying the slurry onto the top surface of the paper mat with a spray nozzle.  
   
   
       9 . The method of  claim 1  wherein the slurry is applied to the paper mat by means selected from the group consisting of curtain coaters, blade coaters, rod coaters, air knife coaters, roll coaters and size presses.  
   
   
       10 . The method of  claim 1  wherein the paper mat is formed by sending pulp and process water to a head box, having the process water deposited from the head box onto a wire screen and removing the paper mat from the wire screen.  
   
   
       11 . The method of  claim 10  wherein the slurry is applied to the paper mat after the paper mat is removed from the wire screen.  
   
   
       12 . A process for making paper comprising the method of  claim 1 .  
   
   
       13 . A process for making paper comprising the method of  claim 10 .  
   
   
       14 . Paper made by the process of  claim 12 .  
   
   
       15 . A dry mix composition that can be applied to a paper mat in the form of a slurry for distribution of one or more heat sensitive papermaking additives within the paper mat comprising from about 90% to less than 100% of an uncooked starch component and between more than zero to no more than about 10% of a heat sensitive papermaking additive.  
   
   
       16 . The composition of  claim 15  wherein the heat sensitive papermaking additives are selected from the group consisting of optical brightening agents, fluorescent agents, dry strength agents, filler particles, sizing agents, flame retardants, pigments and combinations thereof.  
   
   
       17 . The composition of  claim 15  wherein the uncooked starch component is selected from the group consisting of unmodified starch, modified starch, dextrin, maltodextrin and combinations thereof.  
   
   
       18 . The composition of  claim 17  wherein the unmodified starch or modified starch are derived from a source selected from the group consisting of corn, wheat, barley, tapioca, rice, potato and combinations thereof.  
   
   
       19 . A paper mat comprising a slurry of the dry mix composition of  claim 15  and water.  
   
   
       20 . A process for making a dry mix composition comprising the steps of blowing starch into a pneumatic conveyance line having an air pressure of about 60 psi to about 100 psi and adding heat sensitive papermaking additive and optional additive in liquid form into the pneumatic conveyance line wherein the heat sensitive papermaking additive and optional additive are atomizied as the heat sensitive papermaking additive and optional additive enter the conveyance line.