Patent ID: 7520049
Filing Date: 2009-04-21
Classification: C22C,C22F,C23C,C23F,H05B,Y10T

Abstract:
1. A method for manufacturing a planar resistance heating element, said method comprising: a) tempering an aluminum foil deposited on an insulating substrate in a stepwise manner at a temperature of 0 to 40 degree C. for 1.5 to 2.5 hours, thereafter at a temperature of 40 to 70 degree C. for 1.5 to 2.5 hours, thereafter at a temperature of 70 to 100 degree C. for 2.5 to 3.5 hours, and thereafter at a temperature of 100 to 130 degree C. for 14 to 18 hours; b) then etching said aluminum foil in a desired pattern to make a planar resistance heating element; and c) then printing carbon paste and connecting input terminals in parallel to said heating element.