Abstract: The present invention relates to a heat generating sheet which includes a plurality of flat heat generating elements disposed in a plane, and two packaging sheet materials between which the flat heat generating elements are interposed, wherein the two packaging sheet materials each have a boomerang shape and a perforation line from which each packaging sheet material is divided into halves, and the two packaging sheet materials and the flat heat generating elements interposed therebetween are thermocompression-bonded together; and a heat generating sheet bag which includes the heat generating sheet, and an air-impermeable flat bag in which the heat generating sheet is enclosed in a hermetically sealed condition, and more specifically, relates to a heat generating sheet accommodating heat generating elements capable of generating heat by contact with oxygen in air; and a heat generating sheet bag enclosing the heat generating sheet in a hermetically sealed condition.

Abstract: A heating body is provided. The heating body utilizes a heating composition that generates heat when it is brought into contact with oxygen in the air and being controlled easily and correctly in heating temperatures (heating properties). (1) The heating body includes a heating composition housed in a flat air permeable flat bag using an air permeable packaging material formed on one side or both sides thereof. In the heating body, air permeable pores are formed on the packaging material by irradiation of laser rays. The air permeable pores have diameters or circle-corresponding diameters of 0.005 to 2.0 mm. A distance between the centers of the air permeable pores adjacent to each other is 0.1 to 20 mm. The percentage of the area of the air permeable pores to the total area of the laminate sheet is 0.001 to 5%. (2) In the heating body according to the above Item 1, the heating composition may be held by a sheet-like support.

Abstract: The present invention provides an expandable heating sheet which does not lose its expansion property even when a heating composition thereof is hardened due to reaction with oxygen, which can be used while being fitted to a bendable portion such as an elbow or a knee, and which can be easily manufactured with efficiency, and a heating sheet bag in which the expandable heating sheet is hermetically sealed.