Patent ID: 8556108

Claim:
A self-heating system for heating a comestible substance, comprising: a container body defining a volume for holding the comestible substance, the comestible substance having a volume of about 6 fluid ounces to about 12 fluid ounces; a plurality of reactants, said reactants consists essentially of calcium oxide, calcium chloride, magnesium chloride and ethylene vinyl acetate; a reaction chamber disposed adjacent the container body and adapted to house a said plurality of reactants, wherein at least two of the reactants are separated by a rupturable barrier and rupturing of the barrier allows contact between the reactants to form a reaction mixture and initiate a multi-stage exothermic reaction; wherein the exothermic reaction generates sufficient heat during a first stage of the reaction to cause for an initial duration at least a portion of the contents of the reaction chamber to have a temperature of at least 212° F., wherein a portion of the heat from the exothermic reaction is absorbed by the ethylene vinyl acetate, and another portion of the heat is transferred to the comestible substance in the container body, said portion of heat is sufficient to heat the comestible substance from a temperature of about 80° F. to a temperature of about 145° F. within one minute of the initiation of the exothermic reaction; wherein the exothermic reaction is configured to generate a lesser amount of heat during at least a second stage of the exothermic reaction than during the first stage of the exothermic reaction, wherein a portion of the heat generated during the second stage of the reaction is transferred to the comestible substance at a rate that is capable of maintaining the temperature of the comestible substance at or above 145° F. for at least 2 minutes; and wherein the coefficient of heat transfer from the exothermic reaction to the comestible substance is between about 0.0167 BTU/(ft 2 ·sec.·° F.) to 0.0833 BTU/(ft 2 ·sec.·° F.).