Pencil Trace on Cellulose Compounds:A Heat Source

This communication describes a low-cost heater designed and fabricated from materials like paper/ cellulose acetate sheet and a pencil. A high graphite content pencil was used to coat the surface of paper/ cellulose by applying sufficient strokes on the surface. Electrical contacts were made by placing either a wire or copper/aluminium foils over the coated surface. Temperature profile study of the heater indicated that a maximum of 100°C can be achieved without the paper catching fire. The heater was also designed in flexible structure and tested for biomedical purpose. The heater can be operated using a battery, making it easily portable. This makes it useful in school, college and research laboratory experiments with minimum expenses as well as in many medical applications as described.