Absorbent articles with biocompostable properties

Abstract

Disclosed is an absorbent article with biocompostable properties, such as a feminine hygiene pad. Particularly, the present invention is directed to an absorbent sanitary article with a high degree of biocompostability. The sanitary article comprises, in one embodiment, at least a top layer, a back layer, and absorbent core, wherein the absorbent core includes a superabsorbent polymer, and wherein at least the superabsorbent polymer is biocompostable. The absorbent article exhibits improved biocompostable properties and performance comparable to non-biodegradable absorbent articles which include non-biodegradable superabsorbent polymers.

The invention claimed is: 
     
         1 . An absorbent article, comprising:
 a fluid-permeable top layer;   a fluid-resistant back layer; and   an absorbent core;   wherein the absorbent core includes a superabsorbent polymer (SAP);   wherein the SAP includes a modified starch-based biopolymer;   wherein the modified starch-based biopolymer is surface and interior crosslinked; and   wherein the modified starch-based biopolymer has a Free Swell Capacity (FSC) of at least 18 g/g and a Centrifuge Retention Capacity (CRC) of at least 13 g/g in defibrinated sheep's blood.   
     
     
         2 . The article of  claim 1 , wherein the SAP does not include a synthetic polymer and does not include a graft polymer. 
     
     
         3 . The article of  claim 1 , wherein a biobased carbon content of the SAP is at least 50%. 
     
     
         4 . The article of  claim 1 , wherein the SAP is biocompostable. 
     
     
         5 . The article of  claim 1 , wherein the modified starch-based biopolymer includes at least one negatively charged moiety. 
     
     
         6 . The article of  claim 1 , wherein the SAP exhibits no cytotoxicity and is not a dermal irritant. 
     
     
         7 . The article of  claim 1 , wherein the modified starch-based biopolymer is formed using at least two different crosslinking agents, and wherein epichlorohydrin is not used as a crosslinking agent. 
     
     
         8 . An absorbent article, comprising:
 a fluid-permeable top layer;   a fluid-resistant back layer; and   an absorbent core;   wherein the absorbent core includes a superabsorbent polymer (SAP);   wherein the SAP includes a modified biopolymer;   wherein the modified biopolymer is surface and interior crosslinked; and   wherein a biobased carbon content of the SAP is at least 50%.   
     
     
         9 . The article of  claim 8 , wherein the modified biopolymer includes a charge modified biopolymer. 
     
     
         10 . The article of  claim 8 , wherein the modified biopolymer exhibits no cytotoxicity and is not a dermal irritant. 
     
     
         11 . The article of  claim 8 , wherein the modified biopolymer has a Free Swell Capacity (FSC) of at least 18 g/g and a Centrifuge Retention Capacity (CRC) of at least 13 g/g in defibrinated sheep's blood. 
     
     
         12 . The article of  claim 8 , wherein the SAP does not include a synthetic polymer and does not include a graft polymer. 
     
     
         13 . The article of  claim 8 , wherein the modified biopolymer is formed using at least two different crosslinking agents. 
     
     
         14 . The article of  claim 8 , wherein the modified biopolymer is biocompostable. 
     
     
         15 . An absorbent article, comprising:
 a fluid-permeable top layer;   a fluid-resistant back layer; and   an absorbent core;   wherein the absorbent core includes a superabsorbent polymer (SAP);   wherein the SAP includes a modified biopolymer;   wherein the SAP is biobased;   wherein the modified biopolymer is surface and interior crosslinked;   wherein the SAP does not include a synthetic SAP; and   wherein the SAP does not include a graft polymer.   
     
     
         16 . The article of  claim 15 , wherein the modified biopolymer has a Free Swell Capacity (FSC) of at least 18 g/g and a Centrifuge Retention Capacity (CRC) of at least 13 g/g in defibrinated sheep's blood 
     
     
         17 . The article of  claim 15 , wherein the modified biopolymer is synthesized by producing a biopolymer through reactive extrusion using a charge modifying agent and a plasticizer, performing interior crosslinking on the biopolymer, coating the interior crosslinked biopolymer with a surface crosslinking agent, and thermally treating the interior crosslinked biopolymer to create surface crosslinks on the interior crosslinked, charge modified biopolymer. 
     
     
         18 . The article of  claim 15 , wherein a biobased carbon content of the SAP is at least 50%. 
     
     
         19 . The article of  claim 15 , wherein the SAP exhibits no cytotoxicity and is not a dermal irritant. 
     
     
         20 . The article of  claim 15 , wherein the modified biopolymer is biocompostable.