Structure of warmer

Abstract

A unified structure of a warmer is obtained by accommodating an exothermic composition consisting of iron powder, a chloride or sulfate of a metal having a tendency of ionization greater than iron, active carbon and water in a bag composed of a cloth or cloths and a film or films having aeration holes and encapsulating the resulting warmer in an air-tight envelope. Heat of oxidation of iron powder is utilized for the purpose for creating and keeping warmth.

What is claimed is: 
     
       1. A unified structure of a warmer and an air-tight envelope which is used to encapsulate sealingly said warmer at non-service time, said warmer comprising means for enclosing an exothermic composition in contact with water, said means comprising a two layered bag composed of at least one air-permeable cloth layer and at least one impermeable film layer having aeration holes with a predetermined total area and arranged one within the other; said enclosing means being disposed within said air-tight envelope; and said exothermic composition which is activated on contact with air .[.being selected from the group consisting of iron powder, a chloride and a sulfate of a metal having an ionization tendency greater than iron and active carbon.]. .Iadd.comprising iron powder, active carbon and a reaction promoter selected from the group consisting of a chloride and a sulfate of a metal having an ionization tendency greater than iron .Iaddend.filled in said bag, whereby upon opening of said airtight evelope, air contacts said exothermic composition and water to produce heat. 
     
     
       2. A unified structure of claim 1 wherein said film having aeration holes provides the amount of air permeation as measured by the air permeation test according to Frazier type method in the range of 0.5-400 cc/cm 2 . min. 
     
     
       3. A unified structure of claim 1 wherein said cloth is a non-woven fabric. 
     
     
       4. A unified structure of claim 1 wherein said chloride of a metal having an ionization tendency greater than iron is one member selected from the group consisting of KCl, NaCl, CaCl 2  and MgCl 2  in an amount of 0.5-30 parts by weight per 100 parts by weight of iron powder. 
     
     
       5. A unified structure of claim 1 wherein said sulfate of a metal having an ionization tendency greater than iron is one member selected from the group consisting of K 2  SO 4 , Na 2  SO 4 , MgSO 4  and Fe 2  (SO 4 ) 3  in an amount of 2.5-400 parts by weight per 100 parts by weight of iron powder. 
     
     
       6. A unified structure of claim 1 wherein said active carbon has a particle size of 104μ or smaller and is used in an amount of 2.5-400 parts by weight per 100 parts by weight of iron powder. 
     
     
       7. A unified structure of claim 1 wherein water is used in an amount of 30-1,000 parts by weight per 100 parts by weight of iron powder. 
     
     
       8. A unified structure of claim 1 wherein iron powder has a particle size of 200μ or smaller. 
     
     
       9. A unified structure of claim 1 wherein said air-tight envelope is a laminate of synthetic resin films. 
     
     
       10. A unified structure of claim 1 wherein said air-tight envelope is a laminate of a synthetic resin film and an aluminum foil. 
     
     
       11. The structure of claim 1 wherein said cloth layer is disposed within said film layer. 
     
     
       12. The structure of claim 1 wherein said film layer is disposed within said cloth layer. 
     
     
       13. A unified structure of a warmer and an air-tight envelope, said warmer comprising means for enclosing an exothermic composition in contact with water, said means comprising a three layered bag composed of at least one air permeable cloth layer, a stupe layer provided on one side of said bag, and at least one impermeable film layer having aeration holes with a predetermined total area and arranged one within the other; said enclosing means being disposed within said air-tight envelope; and said exothermic composition which is activated in contact with air .[.being selected from the group consisting of iron powder, a chloride and a sulfate of a metal having an ionization tendency greater than iron, and active carbon,.]. .Iadd.comprising iron powder, active carbon and a reaction promotor selected from the group consisting of a chloride and a sulfate of a metal having an ionization tendency greater than iron, .Iaddend.filled in said bag, whereby upon opening of said airtight envelope air contacts said exothermic composition and water to produce heat. 
     
     
       14. A unified structure of claim 13 wherein said air-tight envelope is a laminate of synthetic resin films. 
     
     
       15. A unified structure of claim 13 wherein said air-tight envelope is a laminate of a synthetic resin film and an aluminum foil.