Abstract: The present invention relates to a chemical warmer which comprises an air supply device, a first and a second panel peripherally fastened to each other to form an envelope to contain a chemical thermogenic material. The first panel is configured to include an air-impermeable top layer, an air-permeable middle layer with a plurality of air holes therethrough and an air-permeable inner layer with many micropores therethrough, the top and middle layers being partially welded to each other in such a way that a plurality of air distribution passages and gas exhaust passages are formed for uniformly distributing air inside the panel and extracting exhaust gases/air to a gas exit which is connected to size-adjustable wastegate device. The second panel includes at least an air-impermeable layer. The air supply device is either hand-operated or electronically powered. The present invention further discloses an exothermic material mat which can keep the thermogenic material in place throughout the mat.

Abstract: The present invention relates to a chemical warmer which comprises an air supply device, a first and a second panel peripherally fastened to each other to form an envelope to contain a chemical thermogenic material. The first panel is configured to include an air-impermeable top layer, an air-permeable middle layer with a plurality of air holes therethrough and an air-permeable inner layer with many micropores therethrough, the top and middle layers being partially welded to each other in such a way that a plurality of air distribution passages and gas exhaust passages are formed for uniformly distributing air inside the panel and extracting exhaust gases/air to a gas exit which is connected to size-adjustable wastegate device. The second panel includes at least an air-impermeable layer. The air supply device is either hand-operated or electronically powered. The present invention further discloses an exothermic material mat which can keep the thermogenic material in place throughout the mat.