Circuit elements having an embedded conductive trace and methods of manufacture

Abstract

Disclosed is a circuit element that includes a thermoplastic substrate and a conductive trace at least partially embedded in the thermoplastic substrate. Also disclosed is a method of forming a circuit element. The method includes the steps of providing a thermoplastic substrate having a softening temperature, printing a conductive ink onto the thermoplastic substrate to form a trace, and embedding the trace into the thermoplastic substrate by heating the thermoplastic substrate to a temperature above about the softening temperature about the trace.

1 - 13 . (canceled)  
     
     
         14 . A method of forming a circuit element, the method comprising the steps of: 
 providing a thermoplastic substrate having a softening temperature (T S );    printing a conductive ink onto the thermoplastic substrate to form a trace; and    embedding the trace into the thermoplastic substrate by heating the thermoplastic substrate to a temperature above about the T S .    
     
     
         15 . The method of  claim 14  comprising the step of drying the conductive ink at a temperature less than about the T S  prior to embedding the trace into the thermoplastic substrate.  
     
     
         16 . The method of  claim 14  wherein the step of providing a thermoplastic substrate comprises providing a thermoplastic substrate having a softening temperature (T S ), the thermoplastic substrate having at least one additional substrate disposed adjacent to the thermoplastic substrate.  
     
     
         17 . The method of  claim 14  wherein the step of providing a thermoplastic substrate comprises coextruding a thermoplastic substrate having a Ts, and a second thermoplastic substrate having a second Ts higher that the Ts of the thermoplastic substrate.  
     
     
         18 . The method of  claim 14  comprising the steps of: 
 pre-heating the thermoplastic substrate to a temperature above about the T S ; and  
 allowing the thermoplastic substrate to cool to below about the Ts, prior to printing the conductive ink onto the thermoplastic substrate.  
 
     
     
         19 . The method of  claim 14  comprising the step of embedding the trace into the thermoplastic substrate by localized heating.  
     
     
         20 . The method of  claim 19  comprising the step of embedding the trace into the thermoplastic substrate by induction heating a conductive material in the conductive ink.  
     
     
         21 . The method of  claim 14  comprising the step of flashing off at least a portion of a vehicle of the conductive trace.  
     
     
         22 . The method of  claim 14  comprising the step of conjugating at least a portion of a conductive material in the conductive trace.  
     
     
         23 . The method of  claim 14  comprising the step of cross-linking the thermoplastic substrate after embedding the conductive trace in the thermoplastic substrate.  
     
     
         24 . The method of  claim 23  comprising the step of cross-linking the thermoplastic substrate by electron beam radiation.  
     
     
         25 . The method of  claim 23  comprising the steps of: 
 printing solder onto the thermoplastic substrate;  
 adding electrical components to the thermoplastic substrate; and  
 heating the solder to a reflow temperature.  
 
     
     
         26 . The method of  claim 14  comprising the step of electrolytically plating the conductive trace to form an electrolytic conductive plating disposed on the conductive trace.  
     
     
         27 . The method of  claim 14  comprising the step of coating a surface of the circuit element with a protective coating.  
     
     
         28 . The method of  claim 14  wherein the step of printing a conductive ink onto the thermoplastic substrate to form a trace comprises printing using a printing technique selected from the group consisting of offset-lithographic, flexographic, rotogravure, intaglio, electrophotographic, letterpress, ink jet, laser jet, and combinations thereof.