US Patent 10272221 Humidifier unit

A low cost medical humidifier for adding moisture to a patient air flow is disclosed. The humidifier comprises a water reservoir, a disposable evaporative wick containing a heater, a lid containing electrical contacts to engage the heater in the wick and airway connections. The wick heater comprises a PET film with aluminum tracks and a cover layer of PTC resistive ink. The heater is covered with paper to provide a water pathway via capillary flow. There is a capillary path from the water reservoir to the wick. The wick and heater are manufactured with printing and calendaring processes in reel to reel processes.