Sodium sulfate treated pulp

Abstract

Cellulose pulp sheets treated with sodium sulfate can be fiberized to produce sodium sulfate treated fibers that exhibit desirable densification properties. The sodium sulfate treated fibers densify to a greater degree than fibers that have not been treated with sodium sulfate.

1 . A cellulose pulp sheet comprising: 
 cellulose fibers;    water; and    sodium sulfate applied to the pulp sheet in an amount ranging from about 0.1 to 15 weight percent based on dry fiber weight.    
     
     
         2 . The cellulose pulp sheet of  claim 1 , wherein the sodium sulfate is applied to the pulp sheet in an amount ranging from about 1 to 10 weight percent based on dry fiber weight.  
     
     
         3 . The cellulose pulp sheet of  claim 1 , wherein the cellulose fibers are wood pulp fibers.  
     
     
         4 . The cellulose pulp sheet of  claim 2 , wherein the sodium sulfate is applied to the pulp sheet as an aqueous solution containing about 5 to 33 weight percent sodium sulfate solids.  
     
     
         5 . The cellulose pulp sheet of  claim 4 , wherein the sodium sulfate is applied to the pulp sheet as an aqueous solution containing about 5 to 30 weight percent sodium sulfate solids.  
     
     
         6 . The cellulose pulp sheet of  claim 5 , wherein the sodium sulfate is applied to the pulp sheet as an aqueous solution containing about 5 to 27 weight percent sodium sulfate solids.  
     
     
         7 . The cellulose pulp sheet of  claim 1 , wherein the water content is less than about 20 weight percent based on total product weight.  
     
     
         8 . The cellulose pulp sheet of  claim 7 , wherein the water content is less than about 15 weight percent based on total product weight.  
     
     
         9 . The cellulose pulp sheet of  claim 1 , further comprising an oil.  
     
     
         10 . Treated fibers comprising: 
 cellulose fibers, the cellulose fibers after application and release of a compression load being densified to a first density;    water; and    sodium sulfate, the cellulose fibers after treatment with the sodium sulfate densifying to a second density after application and release of the compression load, the sodium sulfate being present in an amount effective to result in the second density being greater than the first density.    
     
     
         11 . The treated fibers of  claim 10 , wherein the second density is at least 5 percent greater than the first density.  
     
     
         12 . The treated fibers of  claim 11 , wherein the sodium sulfate is present in an amount greater than about 1.0 wt. % based on dry fiber weight.  
     
     
         13 . The treated fibers of  claim 10 , further comprising an oil.  
     
     
         14 . A method for producing a cellulose pulp sheet comprising 
 providing cellulose pulp;    forming a cellulose pulp sheet from the cellulose pulp; and    applying sodium sulfate to the cellulose pulp sheet.    
     
     
         15 . The method of  claim 14 , wherein the cellulose pulp is wood pulp.  
     
     
         16 . The method of  claim 14 , wherein the sodium sulfate is applied to the cellulose pulp sheet in an amount that results in a loading of about 0.1 to 15 weight percent based on dry pulp.  
     
     
         17 . The method of  claim 14 , wherein the sodium sulfate is applied to the cellulose pulp sheet in an amount that results in a loading of about 1.0 to 10 weight percent based on dry pulp.  
     
     
         18 . The method of  claim 14 , wherein the sodium sulfate is applied as an aqueous solution containing from about 5 to 33 weight percent sodium sulfate solids.  
     
     
         19 . The method of  claim 14 , wherein the cellulose pulp sheet further comprises water and the water content of the cellulose pulp sheet after application of the sodium sulfate is less than about 20 weight percent based on total product weight.  
     
     
         20 . The method of  claim 14 , wherein the temperature of the cellulose pulp sheet when the sodium sulfate is applied is at least 25 degrees Celsius.  
     
     
         21 . A method for producing a densified web of cellulose fibers comprising: 
 providing cellulose fibers treated with sodium sulfate;    fiberizing the cellulose fibers treated with sodium sulfate;    forming the fiberized cellulose fibers treated with sodium sulfate into a web; and    compressing the web.    
     
     
         22 . The method  claim 21 , wherein the cellulose fibers are wood pulp fibers.  
     
     
         23 . The method of  claim 21 , wherein the sodium sulfate is present on the cellulose fibers in an amount ranging from about 0.1 to 15 weight percent based on dry fibers.