Tissue Products Incorporating Nanoporous Cellulose Fiber

Abstract

Fibrous cellulosic products incorporating both conventional cellulosic fibers and laterally expanded cellulose fibers exhibit exceptional porosity, bulk, absorbency and resiliency properties. Typical products include absorbent tissue products, absorbent fluff products and flat papers. The laterally expanded cellulose fibers exhibit: (i) a broadened X-Ray diffraction peak for the most prominent reflection having a width at half-height, (W 1/2h ) A , of at least about 3.0° 2Θ, (ii) broad overlapping maxima in their Raman spectrum between 285 and 500 cm −1 , the height of the two tallest of said maxima in said spectrum between 285 and 500 cm −1 being between 35 and 50% of the height of the peak near 1098 cm −1 and (iii) a blue stain when treated with Graff C-stain, the stain exhibiting less red than the stains exhibited with bleached hardwood kraft fibers and bleached softwood kraft fibers.

What is claimed is: 
     
         1 . An assemblage of cellulosic fibers comprising cellulosic fibers other than nanoporous cellulose and nanoporous cellulosic fibers, said nanoporous cellulosic fibers exhibiting, when imaged at high magnification using Environmental Scanning Electron Microscopy (ESEM), a plurality of dark regions having average diameters ranging between about 0.1 and 10 microns. 
     
     
         2 . The assemblage of cellulosic fibers of  claim 1 , wherein at least about 10 8  dark regions are present per square meter of nanoporous cellulosic fibers. 
     
     
         3 . The assemblage of cellulosic fibers of  claim 2 , wherein the average diameter of said plurality of dark regions on said nanoporous cellulosic fibers ranges between about 0.5 and 7 microns. 
     
     
         4 . The assemblage of cellulosic fibers of  claim 1 , wherein the average diameter of said plurality of dark regions on said nanoporous cellulosic fibers ranges between about 0.5 and 7 microns. 
     
     
         5 . The assemblage of cellulosic fibers of  claim 4 , wherein between about 5×10 8  and 10 13  dark regions are present per square meter of nanoporous cellulosic fibers. 
     
     
         6 . The assemblage of cellulosic fibers of  claim 1 , wherein between about 5×10 8  and 10 13  dark regions are present per square meter of nanoporous cellulosic fibers. 
     
     
         7 . The assemblage of cellulosic fibers of  claim 6 , wherein the average diameter of said plurality of dark regions on said nanoporous cellulosic fibers ranges between about 0.5 and 7 microns. 
     
     
         8 . The assemblage of cellulosic fibers of  claim 7 , wherein the average diameter of said plurality of dark regions on said nanoporous cellulosic fibers ranges between about 1 and 5 microns. 
     
     
         9 . The assemblage of cellulosic fibers of  claim 8 , wherein between about 5×10 8  and 10 13  dark regions are present per square meter of nanoporous cellulosic fibers. 
     
     
         10 . The assemblage of cellulosic fibers of  claim 1 , wherein between about 10 9  and 10 12  dark regions are present per square meter of nanoporous cellulosic fibers. 
     
     
         11 . The assemblage of cellulosic fibers of  claim 10 , wherein the average diameter of said plurality of dark regions on said nanoporous cellulosic fibers ranges between about 1 and 5 microns. 
     
     
         12 . The assemblage of cellulosic fibers of  claim 1 , wherein the average diameter of said plurality of dark regions on said nanoporous cellulosic fibers ranges between about 1 and 5 microns. 
     
     
         13 . An assemblage of cellulosic fibers comprising conventional cellulosic papermaking fibers and nanoporous cellulosic fibers, said nanoporous cellulosic fibers exhibiting, when imaged at high magnification using Environmental Scanning Electron Microscopy (ESEM), a plurality of dark regions having average diameters ranging between about 0.1 and 10 microns. 
     
     
         14 . The assemblage of cellulosic fibers of  claim 13 , wherein said conventional cellulosic papermaking fibers are chosen from the group consisting of bleached and unbleached Kraft wood pulp fibers, bleached and unbleached mechanically pulped fibers, chemically pulped hardwood and softwood fibers, recycled fibers, TMP, CTMP, BCTMP and mercerized fibers. 
     
     
         15 . The assemblage of cellulosic fibers of  claim 14 , wherein at least about 10 8  dark regions are present per square meter of nanoporous cellulosic fibers. 
     
     
         16 . The assemblage of cellulosic fibers of  claim 15 , wherein the average diameter of said plurality of dark regions on said nanoporous cellulosic fibers ranges between about 0.5 and 7 microns. 
     
     
         17 . The assemblage of cellulosic fibers of  claim 14 , wherein the average diameter of said plurality of dark regions on said nanoporous cellulosic fibers ranges between about 0.5 and 7 microns. 
     
     
         18 . The assemblage of cellulosic fibers of  claim 17 , wherein between about 5×10 8  and 10 13  dark regions are present per square meter of nanoporous cellulosic fibers. 
     
     
         19 . The assemblage of cellulosic fibers of  claim 14 , wherein between about 5×10 8  and 10 13  dark regions are present per square meter of nanoporous cellulosic fibers. 
     
     
         20 . The assemblage of cellulosic fibers of  claim 19 , wherein the average diameter of said plurality of dark regions on said nanoporous cellulosic fibers ranges between about 0.5 and 7 microns. 
     
     
         21 . An assemblage of cellulosic fibers comprising: (i) cellulosic fibers exhibiting, when imaged at high magnification using Environmental Scanning Electron Microscopy (ESEM), a plurality of darkened regions not apparent on conventional fibers, said darkened regions having average diameters ranging between about 0.1 and 10 microns; and (ii) cellulosic fibers not exhibiting said darkened regions.