To provide a planar heating element capable of suppressing fungal growth and developing heat and its manufacturing method, in particular, to provide an electrothermal element which generates a growth ray and is used for the planar heating element and the planar heating element.
The growth ray hyperthermic device employs the electrothermal element for the planar heating element that has a shape of a cube or a rectangular solid. The electrothermal element comprises black silica 1 dispersed in a composition layer 2 formed by solidifying a graft-polymerized adhesive, provided that Fe is substantially removed from the black silica 1, and that the black silica 1 essentially comprises pieces diced into 0.5-100.0 mm. The electrothermal element for the planar heating element has a function of generating a far-infrared wavelength of 6-14 m when exposed to heat.
Norio Kagami
Jun Komatsu
Hidetake Komatsu