To provide a heat cloth which is thin and flexible; even when as a reaction of an air-permeable heat cloth proceeds, a heat generating composition becomes massive so that flexibility is lowered, or a part of an accommodating bag rides up by shrinkage and
curling as caused by
heat generation, well keeps the bonding and holding state so that it does not fall off easily; is supple like cloths; is excellent in flexing properties; easily and surely fits to flexible places such as elbows and knees; is able to take warmth; is applicable with good follow-up deformation properties to various places of a
human body such as curved parts including shoulders, arms, a neck and feet; and hardly causes an uncomfortable feeling and a process for producing the same.A heat cloth having a heat generating composition molded body resulting from molding a heat generating composition containing surplus water as a connecting substance accommodated in an accommodating bag, wherein the accommodating bag is constituted of a substrate and a covering material; the covering material covers the heat generating composition molded body as provided on the substrate; the periphery of the heat generating composition molded body is heat sealed to form irregularities; sectional exothermic parts of a convex in which the heat generating composition molded body is accommodated are disposed while holding a sectioned part of a concave as a heat seal part; and the exothermic part is formed of a gathering of the sectional exothermic parts, which is characterized in that the substrate is substantially planar and does not contain a pocket, an accommodating division or an accommodating section; that the heat generating composition contains, as essential components, an
iron powder, a carbon component, a reaction accelerator and water, does not contain a flocculant aid, a flocculant, an agglomeration aid, a dry binding material, a dry binding agent, a dry binder, a sticky
raw material, a thickener and an
excipient, contains surplus water so as to have a water mobility value of from 0.01 to 20, with the water in the heat generating composition not functioning as a
barrier layer, and is capable of causing an
exothermic reaction upon contact with air; that a volume of the heat generating composition molded body is from 0.1 to 30 cm3; that a capacity of the sectional exothermic parts to a ratio of the volume of the heat generating composition molded body is from 0.6 to 1.0; that a maximum height of the sectional exothermic parts is from 0.1 to 10 mm; that a width of the sectioned part as a space between the sectional exothermic parts is from 0.3 to 50 mm; that a minimum bending resistance on the surface orthogonal to at least a thickness of the heat cloth is not more than 100 mm; that a part of the accommodating bag has air permeability; and the surroundings of the accommodating bag are sealed.