Abstract: A heat treatment furnace disclosed herein may include: a heat treatment unit configured to heat-treat an object; a cooling unit configured to cool the object heat-treated by the heat treatment unit; and a conveyor configured to convey the object in the heat treatment unit and the cooling unit. The cooling unit may include a housing, wherein the housing is disposed below a conveyance path on which the object is conveyed by the conveyor and configured to cool the object being conveyed by the conveyor by liquid flowing inside the housing. The housing may include an upper plate facing the object being conveyed by the conveyor. The upper plate may be tilted so that gas stays at a predetermined portion of the housing while the liquid is flowing in the housing.

Abstract: An infrared heater 10 includes a heating element 40 that emits infrared radiation when heated and that is capable of absorbing infrared radiation in a predetermined reflection wavelength range, and a filter unit 50 that is disposed so as to be separated by a first space 47, which is open to an outside space, from the heating element 40. The filter unit 50 includes one or more transmission layers (a first transmission layer 51) that transmit at least a part of the infrared radiation from the heating element 40, and a reflective section (the first transmission layer 51) that reflects infrared radiation in the reflection wavelength range toward the heating element 40.

Abstract: A low-temperature drying apparatus includes a furnace body, an object holder, an infrared light transmitting plate, a supply device, a discharge device, and infrared heaters. The object holder holds an object to be dried so that the object to be dried is placed in the furnace body. The infrared light transmitting plate is arranged on a surface of the furnace body that faces the object holder. The cooling flow generating device generates a cooling flow in a space between the object to be dried that is held by the object holder and the infrared light transmitting plate. The infrared heater is disposed to face the infrared light transmitting plate in an open space outside the furnace body.

Abstract: A low-temperature drying apparatus includes a furnace body, an object holder, an infrared light transmitting plate, a supply device, a discharge device, and infrared heaters. The object holder holds an object to be dried so that the object to be dried is placed in the furnace body. The infrared light transmitting plate is arranged on a surface of the furnace body that faces the object holder. The cooling flow generating device generates a cooling flow in a space between the object to be dried that is held by the object holder and the infrared light transmitting plate. The infrared heater is disposed to face the infrared light transmitting plate in an open space outside the furnace body.

Abstract: An infrared heater 10 includes a heating element 40 that emits infrared radiation when heated and that is capable of absorbing infrared radiation in a predetermined reflection wavelength range, and a filter unit 50 that is disposed so as to be separated by a first space 47, which is open to an outside space, from the heating element 40. The filter unit 50 includes one or more transmission layers (a first transmission layer 51) that transmit at least a part of the infrared radiation from the heating element 40, and a reflective section (the first transmission layer 51) that reflects infrared radiation in the reflection wavelength range toward the heating element 40.