Abstract: The present invention provides a measuring apparatus and method for measuring the quantity of ventilation, whereby the quantity of ventilation correlates to the heating characteristics. [The present invention is also] able to measure the quantity of ventilation of a gas permeable packing material used in heating packets in a short period of time, regardless of the type or pore diameter of the packing material. The present invention provides heating packets displaying stable heating characteristics. In the present invention, one surface of a gas permeable packing material is exposed to the atmosphere, while the opposite surface is scavenged with a carrier gas which does not include oxygen. The present invention measures the oxygen diffusing capacity, [as the diffusion of oxygen] from the atmosphere through the gas permeable packing material, by measuring the concentration of oxygen in the carrier gas after scavenging.

Abstract: Provided is a heat generating bag for footwear having a comfortable temperature regardless of the state of use, namely, when staying still, walking etc., which is thin and avoids an uncomfortable feeling of the wearer. The heat generating bag for footwear is made by having a heat generating composition powder and hot-melt adhesive powder held in the pores of multiporous vegetable fiber non-woven fabrics, such fabrics being heat compressed on a mold compressor, and the obtained sheet shaped heat generating body being packed in an air-permeable bag. The heat composition is held in the pores of multiporous vegetable fiber non-woven fabric layers which are superposed by the adhesion of water. Such non-woven fabric are compressed on a mold compressor, and the obtained sheet shaped heat generating body is impregnated with water or an inorganic electrolyte and then packed in an air-permeable bag.

Abstract: The present invention provides a warmer in the form of a sheet shaped heat generating body which is obtained using a warming composition that generates heat when in contact with air, in which the warming composition can be easily dispersed and held in a uniform arrangement, and in which the warming composition is prevented from leaking; and provides a method for manufacturing such a sheet. The sheet shaped heat generating body pertaining to the present invention is obtained by supporting a warming composition and a heat-fusible adhesive powder on a nonwoven fabric (a), superposing a nonwoven fabric (b) on the upper surface, heating and pressing the assembly with the aid of a molding press, and impregnating the resulting sheet with water or an aqueous solution of an inorganic electrolyte.

Abstract: Water is adhered to the bottom face of a non-woven fabric having a large number of pores, then a heat generating powder composition is sprayed onto the top face of this fabric to be held in place. Another non-woven fabric is then superposed on the top face of the first non-woven fabric and the two non-woven fabrics are compressed. Water or a solution of electrolytes in water is then sprayed on the fabrics. Thereby, a sheet shaped heat generating body can be provided which uses a heat generating composition which generates heat when contacting air, which prevents concentration of the heat generating composition in one direction, and which is thin, flexible and has good heat generating properties.