Recording sheet with improved image waterfastness, surface strength, and runnability

Abstract

The present invention relates to a sizing or coating composition that, when applied to paper substrate, creates a substrate having improved waterfastness, surface strength, and surface strength as measured by resistance to abrasion. In addition, the present invention relates to paper substrates containing the composition, as well as methods of using and making the paper substrate and composition.

What is claimed is: 
     
         1 ) A sizing or coating composition, comprising
 at least one binder;   at least one dye fixative; and   at least one crosslinking agent.   
     
     
         2 ) sizing or coating composition according to  claim 1 , further comprising at least one pigment.) 
     
     
         3 .) The sizing or coating composition according to  claim 1 , further comprising at least one inorganic salt.) 
     
     
         4 .) The composition according to  claim 1 , wherein the at least one binder is present at an amount ranging from 85 to 98 wt % based upon the total weight of the solids in of the composition.) 
     
     
         5 .) The composition according to  claim 1 , wherein the at least one dye fixative is present at an amount ranging from 0.5 to 10 wt % based upon the total weight of the starch in of the composition.) 
     
     
         6 .) The composition according to  claim 1 , wherein the at least one crosslinking agent is present at an amount ranging from 0.5 to 5 wt % based upon the total weight of the starch in of the composition.) 
     
     
         7 .) The composition according to  claim 1 , wherein the at least one binder is at least one member selected from the group consisting of starch, modified starch and polyvinyl alcohol. 
     
     
         8 .) The composition according to  claim 1 , wherein the at least one dye fixative is at least one member selected from the group consisting of a polyamine, a polyeneimine, and an optical brightening agent:nitrogen-containing compound complex.) 
     
     
         9 .) The composition according to  claim 1 , wherein the at least one crosslinking agent is at least one member selected from the group consisting of glyoxal and blocked glyoxal.) 
     
     
         10 .) The composition according to  claim 1 , comprising
 the at least one binder at an amount of 85 to 98 wt % based upon the total weight of the solids in of the composition;   at least dye fixative at an amount ranging from 0.5 to 10 wt % based upon the total weight of the starch in of the composition; and   at least one crosslinking agent at an amount ranging from 0.25 to 5 wt % based upon the total weight of the starch in of the composition.   
     
     
         11 .) The composition according to  claim 10 , wherein
 the at least one binder is selected from the group consisting of starch and polyvinyl alcohol;   the at least one dye fixative is selected from the group consisting of a polyamine, a polyeneimine, and an optical brightening agent:nitrogen-containing compound complex; and   the at least one crosslinking agent is selected from the group consisting of glyoxal and blocked glyoxal.)   
     
     
         12 . A paper substrate, comprising the composition according to  claim 11 . 
     
     
         13 . The paper substate according to  claim 12 , comprising an effective amount of the composition such that the substrate has a waterfastness as measured by DL % of from −10 to 15. 
     
     
         14 .) The paper substate according to  claim 12 , comprising an effective amount of the composition such that the substrate has a waterfastness as measured by DL % is from 5 to 55. 
     
     
         15 .) The paper substrate according to  claim 12 , comprising an effective amount of the composition such that the substrate has a surface strength that is less than 60 mg/1000 revolutions as measured by the Taber Abrasion test.) 
     
     
         16 .) The paper substrate according to  claim 12 , comprising an effective amount of the composition such that the substrate has a surface strength that is less than 50 mg/1000 revolutions as measured by the Taber Abrasion test.) 
     
     
         17 .) The paper substrate according to  claim 12 , comprising an effective amount of the composition such that the substrate has a surface strength that is less than 40 mg/1000 revolutions as measured by the Taber Abrasion test.) 
     
     
         18 .) The paper substrate according to  claim 12 , comprising an effective amount of the composition such that the substrate; when in a roll that is 36 inches wide, 50 inches in diameter, and having a 3 inch core, runs continuously for greater than half of a total length of the roll.) 
     
     
         19 .) The paper substrate according to  claim 12 , comprising an effective amount of the composition such that the substrate; when in a roll that is 36 inches wide, 50 inches in diameter, and having a 3 inch core, runs continuously for at least two lengths of the roll.) 
     
     
         20 .) A method of making the paper substrate according to  claim 12 , comprising contacting a web of fibers with the composition at a size press or at a coater.