Crosslinking cellulose with glyoxal to improve absorption properties

Abstract

The present invention is directed to a novel dialdehyde based reagent that is neutralized, wherein the preparation of the reagent includes the steps of provide a dialdehyde; provide a caustic soda; mix both reagents until pH of the dialdehyde is 5.5 to 7.5; and stir the mixture.

1 . A dialdehyde based reagent, wherein the preparation of the reagent comprises:
 a. provide a dialdehyde in water,   b. provide caustic soda;   c. add caustic soda until pH of the dialdehyde is 5.5 to 7.5; and   d. stir the mixture.   
     
     
         2 . The dialdehyde based reagent of  claim 1 , wherein the reagent is suitable for making liquid surge fiber. 
     
     
         3 . The dialdehyde based reagent of  claim 2 , wherein the surge fiber pulp is useful for use as a surge layer in an absorbent article. 
     
     
         4 . The dialdehyde based reagent of  claim 1 , wherein the reagent is formed from reacting glyoxal compound and a sodium hydroxide compound. 
     
     
         5 . The dialdehyde based reagent of  claim 4 , wherein the glyoxal compound is water soluble or form water soluble products when reacted with sodium hydroxide. 
     
     
         6 . The dialdehyde based reagent of  claim 5 , wherein the dialdehyde is selected from glyoxal, glutaraldehyde, 1,4-cyclohexane dicarbaldehyde, and 1,3-cyclohexane dicarbaldehyde, and mixtures thereof. 
     
     
         7 . The dialdehyde based reagent of  claim 1 , wherein the caustic soda is sodium hydroxide or potassium hydroxide. 
     
     
         8 . The dialdehyde glycol based reagent of  claim 4 , wherein the reaction between dialdehyde and sodium hydroxide is carried at a temperature ranges from room temperature for at least 10 min. 
     
     
         9 . A method of making liquid surge fiber, comprising: providing a solution of the dialdehyde based cross-linking reagent of  claim 1 ; diluting the solution; providing cellulosic fiber; applying the solution of the dialdehyde reagent to cellulosic fibers to impregnate the cellulosic based fibers; and drying the treated cellulosic fibers. 
     
     
         10 . The method of  claim 9 , wherein the solution of the dialdehyde based reagent has a pH of about 5.5 to 7.5. 
     
     
         11 . The method of  claim 9 , wherein the solution of the dialdehyde based reagent is applied to the cellulosic based fiber by spraying, dipping or applying with a puddle press, size press or a blade-coater. 
     
     
         12 . The method of  claim 9 , wherein the cellulosic fiber is provided in sheet or roll form. 
     
     
         13 . The method of  claim 9 , wherein the solution of the reagent is applied to the cellulosic fibers to provide 1 wt % to about 3 wt % of dialdehyde based crosslinking reagent on fiber. 
     
     
         14 . The method of  claim 9 , wherein the cellulosic based fiber is provided in a dry state or a never dried state. 
     
     
         15 . The method of  claim 9 , wherein the cellulosic based fiber is a conventional cellulose fiber selected from the group consisting of: hardwood cellulose pulp, softwood cellulose pulp obtained from a kraft or sulfite chemical process, caustic-treated pulp and combinations and mixtures thereof. 
     
     
         16 . The method of  claim 9 , wherein the pulp after treatment is dried. 
     
     
         17 . The method of  claim 16 , wherein the drying is conducted at a temperature within the range of about 120° C. to about 160° C. 
     
     
         18 . The method of  claim 16 , wherein the treated pulp is dried for a period that affords pulp with a moisture content of less than 7%. 
     
     
         19 . A cellulose fiber which is crosslinked by the dialdehyde based reagent of  claim 1 . 
     
     
         20 . An article of manufacture comprising the cellulose fiber of  claim 19 .