Apparatus for assisting in the curing of concrete and for heating

Claim 1

A flexible rollable heat control blanket comprising: a first layer Composed of a thin, flexible, moisture-impervious, heat-conductive and electrically-insulative plastic material; a second layer contiguous with said first layer and composed of a thin, flexible and electrically conductive material productive of heat in response to the application of an electric potential across opposing edge portions thereof; a third layer contiguous with said second layer and composed of a thin, flexible moisture-impervious and electrically insulative plastic material, at least one of said first and third layers being of the color black so as to inhibit penetration of electromagnetic waves in the ultraviolet and near-ultraviolet region of the spectrum; a fourth layer contiguous with said third layer and composed of a comparatively substantially thicker, flexible heat-insulative and resilient material of foam vinyl substance, the exposed surface of said fourth layer opposite said third layer being of a very light color including one of the colors yellow and white so as to be substantially reflective to electromagnetic waves in the visible region of the spectrum; and a flexible reinforcing web, composed of interlaced strings of nylon exhibiting substantial tensile strength, buried within said foam vinyl substance and spaced from and generally parallel to said exposed surface and said third layer.