Active Iron Powder And Heat Generating Body

Abstract

There is provided an active iron powder which is suitable as a raw material of a heat generating body, is excellent in rising properties of a heat generating composition and is excellent in economy. The invention is concerned with an active iron powder to be contained in a heat generating composition capable of generating heat upon contact with air, characterized in that an amount of wustite to be contained in an iron powder is from 5.01 to 50% by weight in terms of an X-ray peak intensity ratio to iron.

1 . An active iron powder to be contained in a heat generating composition capable of generating heat upon contact with air, characterized in that an amount of wustite to be contained in an iron powder is from 5.01 to 50% by weight in terms of an X-ray peak intensity ratio to iron.  
   
   
       2 . The active iron powder according to  claim 1 , characterized in that the active iron powder is at least one member selected from a reduced iron powder, an atomized iron powder, and an iron powder comprising particles, a surface of each of which is at least partially covered by a conductive carbonaceous substance.  
   
   
       3 . A heat generating composition containing as essential components containing an iron active powder according to  claim 1 , a carbon component, a reaction accelerator and water, characterized in that the active iron powder accounts for from 30 to 100% by weight of the iron powder in the heat generating composition.  
   
   
       4 . A heat generating body, characterized by containing the heat generating composition according to  claim 3 .  
   
   
       5 . The heat generating body according to  claim 4 , characterized in that the heat generating body has fixing means in at least a part thereof.  
   
   
       6 . The heat generating body according to  claim 5 , characterized in that the fixing means is an adhesive layer; and that the adhesive layer contains at least one member selected from additional components consisting of a water retaining agent, a water absorptive polymer, a pH adjusting agent, a surfactant, an organosilicon compound, a hydrophobic polymer compound, a pyroelectric substance, an antioxidant, an aggregate, a fibrous material, a moisturizer, a functional substance, and a mixture thereof.