Heat generating body, heat insulating method using the same and packaging material for die molding heat generation

1. A heat generating body wherein a heat generating composition molded body resulting from molding a moldable heat generating composition containing surplus water as a connecting substance is interposed between packaging materials and the periphery of the heat generating composition molded body is heat sealed, characterized in that:

1) the packaging materials are each constituted of a substrate and a covering material,

2) the substrate, which is substantially planar and does not have an accommodating pocket, has a structure to cover a heat generating composition with the covering material after mounting the heat generating composition on the substantially planar substrate,

3) the packaging materials each has a bending resistance of not more than 100 mm,

4) the packaging materials are each a non-elastic body at least at a temperature between 25° C. and 60° C., has a breaking strength of 500 g/mm 2 or more at 25° C. and has a breaking elongation of 30% or more at 90° C.,

5) the moldable heat generating composition contains, as essential components, an iron powder, a carbon component, a reaction accelerator and water, has a water content of from 1 to 60% by weight, does not contain a flocculant aid, a flocculant, an agglomeration aid, a dry binder, a dry binding agent, a dry binding material, a sticky raw material, a thickener and an excipient, contains the surplus water so as to have a water mobility value of from 0.01 to 20, has moldability due to the surplus water, with the water in the moldable heat generating composition not functioning as a barrier layer, and is capable of causing an exothermic reaction upon contact with air,

6) plural sectional exothermic parts as divided by a sectioned part which is formed by heat sealing are provided,

7) the heat generating body contains a region wherein the ratio of the bending resistance in a first direction orthogonal to the thickness direction of the heat generating body, to the bending resistance in a second direction orthogonal to the thickness direction of the heat generating body and orthogonal to the first direction, is 2 or more,

8) at least a part of the heat generating body has permeability to air, and

9) the heat generating body has a fixing measure on at least a part of the exposed surface thereof.

2. The heat generating body according to claim 1 , characterized in that the packaging materials are each constituted of a laminate of a fibrous material and a film; and that a raw material of each of the fibrous material and the film is a material made of polyethylene inclusive of one as produced using a metallocene catalyst, polypropylene, a nylon, a polyester, polyvinyl chloride, polyvinylidene chloride, polyurethane, polystyrene, a saponified ethyl-ene-vinyl acetate copolymer, an ethylene-vinyl acetate copolymer, a natural rubber, a regenerated rubber, a synthetic rubber, or a mixture thereof.

3. The heat generating body according to claim 2 , characterized in that the fibrous material is a non-woven fabric; that the film is a polyethylene-made porous film; and that the non-woven fabric and the polyethylene-made porous film are laminated via an air-permeable sticky layer.

4. The heat generating body according to claim 1 , characterized in that the substrate or the covering material is non-shrinkable at 90° C.

5. The heat generating body according to claim 1 , characterized in that the packaging materials each has a breaking elongation of 100% or more at 90° C.

6. The heat generating body according to claim 1 , characterized in that the heat generating composition contains at least one member selected from additional components consisting of a water retaining agent, a water absorptive polymer, a pH adjusting agent, a hydrogen formation inhibitor, an aggregate, a fibrous material, a functional substance, a surfactant, an organo-silicon compound, a pyroelectric substance, a moisturizer, a fertilizer component, a hydrophobic polymer compound, a heat generating aid, a metal other than iron, a metal oxide other than iron oxide, an acidic substance, and a mixture thereof.

7. The heat generating body according to claim 1 , characterized in that the heat seal part is heat sealed after temporary adhesion by an adhesive layer; and that an adhesive component which constitutes the adhesive layer and a component of a heat sealing material which constitutes the heat seal layer are copresent in the heat seal part.

8. A packaging material for die molding which is used in the heat generating body according to claim 1 , characterized in that the packaging material is a non-elastic body at least at a temperature between 25° C. and 60° C., has a breaking strength of 500 g/mm 2 or more at 25° C. and has a breaking elongation of 30% or more at 90° C. and is made of a thermoplastic resin-made fibrous material and a thermoplastic resin-made film.