Method of producing electrothermal filament containing carbon black and the product of the method

Abstract

A method of producing electrothermal filament containing carbon black that first grafts carbon black to monomer to form grafted copolymer. Then, the grafted copolymer is coated around the filament to form a conductive core. Lastly, membrane is laminated around the conductive core to protect and insulate the core.

What is claimed is:  
     
         1 . A method of producing electrothermal filament containing carbon black, the method comprising following acts: 
 obtaining carbon black, a grafting monomer, an initiator, a terminating agent, nitrogen gas and rolls of a membrane;    grafting the carbon black with monomers by mixing the carbon black with the grafting monomer and initiator to graft the carbon black to the monomer to form grafted copolymers and then adding a terminating agent to the mixture to stop the grafting;    coating the filaments with the grafted copolymers by passing the filaments through the grafted copolymers to apply a layer of carbon black on the filaments; and    laminating membranes on the filament.    
     
     
         2 . The method of producing electrothermal filament containing carbon black as claimed in  claim 1 , wherein 
 the monomer is styrene;    the initiatior is a 0.5˜2% benzoyl peroxide solution;    the terminating agent is acetone;    the membranes are soft and flexible material selected from the group comprising polyethylene (PE) or thermoplastic urethane (TPU) elastomer; and    the carbon black proportion is 8˜15%;    the styrene monomer is 80˜90%; and    the remaining component is benzoyl peroxide solution.    
     
     
         3 . The method of producing electrothermal filament containing carbon black as claimed in  claim 2 , wherein the carbon black, styrene monomer, and benzoyl peroxide are mixed to form a grafted copolymer; 
 wherein nitrogen gas is added to maintain a temperature of 60° F. for 6 to 8 hours.    
     
     
         4 . The method of producing electrothermal filament containing carbon black as claimed in  claim 1 , where the act of coating the filaments with the grafted copolymer comprises passing the filament through the grafted copolymer three times to ensure sufficient carbon black is on the filament.  
     
     
         5 . The method of producing electrothermal filament containing carbon black as claimed in  claim 1  further comprising the act of respectively attaching two electrodes to opposite ends of each electrothermal filament.  
     
     
         6 . An electrothermal filament in accordance with the present invention comprising: 
 grafted copolymer formed by grafting carbon black to a monomer;    a filament having two ends coated with the grafted copolymer; and    a membrane laminated on the filament having the grafted copolymer as insulation.    
     
     
         7 . The electrothermal filament as claimed in  claim 6 , wherein the electrothermal filament further has two electrodes respectively attached to opposite ends of the electrothermal filament.