| 摘要 |
<p>PURPOSE:To obtain the title material for warming having a persistent high peak temperature by enclosing a composition which contains a metal powder, a metal halide, and water and generates heat when in contact with air in a packaging material having a specified gas permeability. CONSTITUTION:The title material is obtained by enclosing a heat generating composition obtaining a metal powder (e.g. an iron powder, preferably a porous reduced iron powder having a particle diameter of 44-350mum), a metal halide (e.g. NaCl), and water in a packaging material having a Gurley gas permeability which satisfies the relation: 0.5cc/cm<2>.sec >=A+B>=0.1cc/cm<2>.sec (wherein A is the gas permeability of one side of the packaging material; B is that of the other side thereof) (e.g. one obtained by the fusion of a perforated polyethylene-laminated Japanese paper with a polyethylene-laminated aluminum foil). The water content of the composition is 5-25wt.%, preferably 10-20wt.%, and the metal halide content thereof is 3-15wt.%, preferably 5-10wt.%.</p> |
