Abstract: A water activated therapeutic moist heat pad structure is described formed with outer porous water retaining layers which enclose an inner layer of distributed heat generating heat cells and an associated water retaining absorbent inner porous layer. In a preferred embodiment the heat cells are formed of electrochemical heat cells wherein a suitable dry electrolyte is provided such as table salt. The inner porous layer is sized to provide the electrochemical heat cells with adequate electrolyte to use up their active ingredients and achieve an extended heating period. The segmentation of the heat cells and their distribution throughout the structure combine to provide a flexible therapeutic moist heating pad which can conform to the body surface to be treated.

Abstract: A self-contained warming pad characterized by a heating element, an adjacent dose of activating liquid within a frangible container, and a substantially liquid-impervious cover enclosing the element and frangible container and having at least one tortuous air passage therethrough. Features include a cover having thermal insulating qualities, and a frangible container made of a meltable substance having a melting point chosen to control the upper temperatures of the pad. Other features relate to a cover configuration which provides an annular breathing passage, and a porous resilient mass within the pad which provides a substantial breathing capacity. The heating element is preferably an electrochemical element, and most preferably a complex electrochemical element having two cathode layers and one anode layer in a sandwich-like structure.

Abstract: An improvement in the separator layer of an electrochemical heating element having two electrode layers, a separator layer of porous, absorbent material therebetween, and electrically conductive connector means extending through the electrode and separator layers. The improved device includes structural spacing means interposed between one of the electrode layers and at least a portion of the other electrode layer to limit compression of the separator layer material. In one embodiment, discrete mechanical spacers are placed immediately adjacent to the connector means. In another embodiment, a recessed surface portion is formed in one of the electrode layers and the adjacent separator layer has a mating portion on one side which is received into the recessed surface portion.BACKGROUND OF THE INVENTIONThis invention relates to electrochemical heat-generating elements, and, in particular, to improvements in uniformity and performance reproducibility in such elements.The prior art as taught by Kober in U.S. Pat.