Patent ID: 7562661

Claim:
A hair warming tool of sheet form comprising: at least one heating part in the center thereof, the heating part including a heat generating material which contains iron powder and generates heat upon contact with air; and a margin disposed around said heating part, said margin being free of the heat generating material and configured to wrap hair adjacent to said heating part and to be held in place to maintain a wrapped state by a fastener connected to said margin, wherein the hair warming tool includes first and second sides, each of the first and second sides having a surface area of from 100 to 1200 cm 2 , and the hair warming tool further includes an outermost base sheet adapted to contact said wrapped hair when in the wrapping state, said outermost base sheet comprising a water resistant material, said outermost base sheet being non-removably attached to said hair warming tool and the margin includes a seal at an outer perimeter of the margin, and the margin further includes a portion between the seal and the heating part, the portion including a first sheet separated from the outermost base sheet by an air gap, wherein a total area of the heating part, as viewed from the first side, extends across 10% to 40% of the surface area of the first side, and wherein a width of the margin as measured from an edge of the hair warming tool to the nearest heating part extends from 3 to 15 cm over a periphery of the hair warming tool.