Waste encapsulating animal litter

Abstract

Disclosed herein is a method for encapsulating solid animal waste with animal litter to eliminate the odor that emanates from the waste material. An additional benefit is that encapsulation hides the solid waste from view. The encapsulated waste resembles a urine clump in the litter box. Waste-encapsulating actives are incorporated in the litter composition to provide this benefit.

1 . An animal litter comprising:
 an absorbent material suitable for use as an animal litter and at least one waste-encapsulating system that enables encapsulation of solid animal waste and/or urine clumps;   wherein said waste encapsulating system comprises:   (1) a water reactive polymer as a binder,   (2) an acidic solid material, and   (3) a carbonate-containing or percarbonate-containing solid material.   
   
   
       2 . The animal litter recited in  claim 1 , further comprising a stabilizer. 
   
   
       3 . The animal litter recited in  claim 1 , wherein the at least one waste-encapsulating system functions at low moisture levels and has a binding effect. 
   
   
       4 . The animal litter recited in  claim 1 , wherein the at least one waste encapsulating system has a high water vapor transport and a low organic vapor transport. 
   
   
       5 . The animal litter recited in  claim 1 , wherein the at least one waste-encapsulating system is activated by contact with moisture. 
   
   
       6 . The animal litter recited in  claim 1 , wherein the acidic solid is water soluble. 
   
   
       7 . The animal litter recited in  claim 6 , wherein the water soluble acidic solid is citric acid, malic acid, fumaric acid, boric acid, or combinations thereof. 
   
   
       8 . The animal litter recited in  claim 1 , wherein the carbonate-containing or percarbonate-containing solid is limestone, sodium bicarbonate, but potassium bicarbonate, calcium carbonate, magnesium carbonate, carbonates, sodium percarbonate (2Na2CO3.3H2O), or combinations thereof. 
   
   
       9 . The animal litter recited in  claim 1 , wherein the water reactive polymer is a modified starch. 
   
   
       10 . The animal litter recited in  claim 2  wherein the stabilizer is a surfactant, silica powder or bentonite powder. 
   
   
       11 . A method for controlling the odor that emanates from animal waste comprising:
 providing the animal litter recited in  claim 2 ;   contacting the animal litter with a moisture containing solid animal waste and/or urine clump;   dissolving the acidic solid material with moisture contained in the solid animal waste and/or urine clump to initiate a gas-generating reaction;   creating a foam from the gas-generating reaction between the solid acid and the carbonate-containing or percarbonate-containing solid perpetuating the gas-generating reaction by creating water from the reaction between the solid acid and the carbonate-containing or percarbonate-containing solid;   substantially encapsulating the solid animal waste and/or urine clump with the foam produced by the gas-generating reaction;   creating a structural network within the foam to give the foam longevity and shape;   providing structural integrity to the foam shape as the foam dries; and   creating a dry foam that encapsulates the solid animal waste and/or urine clump with a shell of animal litter wherein the shell has a thickness of at least 1 mm to physically block the emanation of odor from the waste and/or clump.   
   
   
       12 . The method recited in  claim 11 , further comprising the step of:
 covering the solid animal waste or urine clump with the animal litter.   
   
   
       13 . The method recited in  claim 11 , wherein the surfactant creates the structural network within the foam to give the foam longevity and shape and the water reactive polymer provides structural integrity to the foam shape as the foam dries. 
   
   
       14 . The method recited in  claim 11 , wherein the water reactive polymer is a modified starch. 
   
   
       15 . The method recited in  claim 11 , wherein the water created from the reaction between the solid acid and the carbonate-containing or percarbonate-containing solid perpetuates a continuous reaction that enables waste-encapsulation in low moisture environments. 
   
   
       16 . The method recited in  claim 11 , wherein encapsulation of solid waste and/or urine clumps results in a Malodor Score less than 23. 
   
   
       17 . The method recited in  claim 11 , wherein encapsulation of solid waste and/or urine clumps results in a Malodor Score less than 27½. 
   
   
       18 . An animal litter comprising:
 at least one absorbent material suitable for use as an animal litter; and   at least one waste-encapsulating active that enables encapsulation of solid animal waste,   wherein the at least one waste-encapsulating active upon contact with solid animal waste creates a shell of animal litter having a thickness of at least 1 mm substantially encapsulating said waste, wherein said shell physically blocks the emanation of odor from the waste.   
   
   
       19 . The animal litter recited in  claim 19 , wherein the waste-encapsulating active is selected from the group consisting of water reactive polymers, water soluble film-forming and gel-forming polymers, derivatives of water soluble film-forming and gel-forming polymers, and combinations thereof. 
   
   
       20 . The animal litter recited in  claim 19 , wherein the waste-encapsulating active is a crosslinkable, water soluble film-forming and gel-forming polymer selected from the group consisting of polyethylene oxide, polyvinyl pyrrolidone, polyvinyl alcohol, polyethylene glycol, polyacrylic acid and combinations thereof and wherein the animal litter further comprises at least one cross-linking agent.