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.

What is claimed is: 
     
         1 . A disposable absorbent sanitary 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 a biobased carbon content of the SAP is at least approximately 80%; and   wherein the modified starch-based biopolymer has a Free Swell Capacity (FSC) of at least about 18 g/g and a Centrifuge Retention Capacity (CRC) of at least about 13 g/g in defibrinated sheep's blood.   
     
     
         2 . The article of  claim 1 , wherein the SAP does not include a synthetic polymer. 
     
     
         3 . The article of  claim 1 , wherein the SAP does not include a graft polymer. 
     
     
         4 . The article of  claim 1 , wherein the article is a menstrual pad. 
     
     
         5 . The article of  claim 1 , wherein a ratio of the SAP to fluff in the absorbent core is approximately 10 to approximately 90. 
     
     
         6 . The article of  claim 1 , wherein a ratio of the SAP to fluff in the absorbent core is approximately 25 to approximately 75, and wherein the primary rewet under load of the article is less than about 2.0 grams in defibrinated sheep's blood according to modified NWSP 070.8.R1. 
     
     
         7 . The article of  claim 6 , wherein the secondary rewet under load of the article is less than about 3.50 grams in defibrinated sheep's blood according to modified NWSP 070.8.R1. 
     
     
         8 . The article of  claim 1 , wherein the liquid absorption capacity of the article is at least approximately 1150% in defibrinated sheep's blood. 
     
     
         9 . The article of  claim 1 , wherein the modified starch-based biopolymer includes a charge modified starch-based biopolymer including at least one negatively charged moiety. 
     
     
         10 . The article of  claim 1 , wherein a ratio of the SAP to fluff in the absorbent core is approximately 10 to approximately 90, with the absorbent core having a density of approximately 0.23 g/cm3. 
     
     
         11 . The article of  claim 1 , wherein the article, including the SAP, is biocompostable or biodegradable. 
     
     
         12 . The article of  claim 1 , wherein the absorbent core uptakes more defibrinated sheep's blood than an absorbent core with the same SAP to fluff ratio, the same density, and the same weight of a polyacrylate based SAP as the weight of the modified biopolymer over 30 minutes on a board placed at a 30-degree tilt dipped into 500 mL of the defibrinated sheep's blood. 
     
     
         13 . The article of  claim 1 , wherein the modified starch-based biopolymer is formed using at least two different crosslinking agents. 
     
     
         14 . A disposable absorbent sanitary 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 biodegradable;   wherein a biobased carbon content of the SAP is at least approximately 84%; and   wherein the article is a menstrual pad.   
     
     
         15 . The article of  claim 14 , wherein a ratio of the SAP to fluff in the absorbent core is approximately 10 to approximately 90, with the absorbent core having a density of approximately 0.23 g/cm 3 . 
     
     
         16 . The article of  claim 14 , wherein the primary rewet under load of the article is less than about 2.00 grams and the secondary rewet under load of the article is less than about 3.50 grams in defibrinated sheep's blood according to modified NWSP 070.8.R1 
     
     
         17 . The article of  claim 14 , wherein the modified biopolymer is made from potato starch, pea starch, corn starch, and/or tapioca starch. 
     
     
         18 . The article of  claim 14 , wherein the modified starch-based biopolymer has a Free Swell Capacity (FSC) of at least about 18 g/g and a Centrifuge Retention Capacity (CRC) of at least about 13 g/g in defibrinated sheep's blood. 
     
     
         19 . A disposable absorbent sanitary 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 SAP is biodegradable and biobased;   wherein the SAP does not include a synthetic SAP;   wherein the SAP does not include a graft polymer; and   wherein the modified starch-based biopolymer has a Free Swell Capacity (FSC) of at least about 18 g/g and a Centrifuge Retention Capacity (CRC) of at least about 13 g/g in defibrinated sheep's blood.   
     
     
         20 . The article of  claim 19 , wherein the absorbent core uptakes more defibrinated sheep's blood than an absorbent core with the same SAP to fluff ratio, the same density, and the same weight of a polyacrylate based SAP as the weight of the modified biopolymer over 30 minutes on a board placed at a 30-degree tilt dipped into 500 mL of the defibrinated sheep's blood.