A disposable warmer of the present invention has a bag including a bag member (A) and a bag member (B); a heater; a heat-sealed portion where the bag member (A) and the bag member (B) are heat-sealed; and a portion with the heater sealed therein. The bag members (A) and (B) are heat-sealed with each...http://www.google.es/patents/US7950385?utm_source=gb-gplus-sharePatente US7950385 - Disposable warmer and bag member for the same
