Stretchable conductive fluoroelastomer paste composition

Abstract

The invention relates to a polymer thick film (PTF) conductive paste composition comprising a conductive powder, a fluoroelastomer, a silane coupling agent, and one or solvents. The PTF conductive paste composition can be used to form a printed conductor and to form an electrically conductive adhesive on various articles. The PTF conductive paste composition is provides a stretchable electrical conductor for wearables.

What is claimed is: 
     
         1 . A polymer thick film conductive paste composition comprising:
 a) 45-65 wt % conductive powder;   b) 10-20 wt % fluoroelastomer;   c) 0.1-3 wt % silane coupling agent;   d) 0-35 wt % of one or more solvents selected from the group consisting of 2-(2-ethoxyethoxy)ethyl acetate, diethylene glycol monobutyl ether acetate, ethylene glycol diacetate, dibasic esters and c11; and   e) 1-35 wt % of one or more solvents selected from the group consisting of triethyl phosphate, acetone, 4-methyl-2-pentanone, 2,6-dimethyl-4-heptanone and cyclohexane, wherein the wt % are based on the total weight of the paste composition.   
     
     
         2 . The polymer thick film conductive paste composition of  claim 1 , wherein the fluoroelastomer is a vinylidene fluoride containing fluoroelastomer copolymer. 
     
     
         3 . The polymer thick film conductive paste composition of  claim 2 , wherein the fluoroelastomer is a terpolymer of vinylidene fluoride, hexafluoropropylene and tetrafluoroethlyene. 
     
     
         4 . The polymer thick film conductive paste composition of  claim 2 , wherein the fluoroelastomer is a dipolymer of vinylidene fluoride and hexafluoropropylene. 
     
     
         5 . The polymer thick film conductive paste composition of  claim 1 , wherein the conductive powder is an electrically conductive powder of one or more of Ag, Cu, Au, Pd, Pt, Sn, Al, Ni, C, alloys thereof and mixtures thereof. 
     
     
         6 . The polymer thick film conductive paste composition of  claim 5 , wherein the conductive powder is silver powder 
     
     
         7 . The polymer thick film conductive paste composition of  claim 6 , wherein the silver powder is in the form of silver flakes. 
     
     
         8 . The polymer thick film conductive paste composition of  claim 1 , wherein the silane coupling agent is selected from the group consisting of [3-(2,3-epoxypropoxy)propyl]trimethoxysilane (3-glycidyloxypropyltrimethoxysilane), (am inopropyl)trimethoxysilane, (methacryloxypropyl)trimethoxysilane, (vinyl)trimethoxysilane and (mercaptopropyl)trimethoxysilane. 
     
     
         9 . The polymer thick film conductive paste composition of  claim 8 , wherein the silane coupling agent is [3-(2,3-epoxypropoxy)propyl]trimethoxysilane. 
     
     
         10 . The polymer thick film conductive paste composition of  claim 1 , comprising 0-35 wt % of 2-(2-ethoxyethoxy)ethyl acetate and 1-35 wt % of triethyl phosphate 
     
     
         11 . An article comprising a printed conductor formed from the polymer thick film conductive paste composition as in  claim 1 . 
     
     
         12 . The article of  claim 11 , wherein the article is a wearable garment. 
     
     
         13 . The article of  claim 12 , wherein the printed conductor is printed on a substrate which has been subsequently laminated to the garment. 
     
     
         14 . The article of  claim 11 , wherein the article has been thermoformed and subsequently subjected to injection molding. 
     
     
         15 . An article comprising a printed conductive adhesive formed from the polymer thick film conductive paste composition as in  claim 1 . 
     
     
         16 . The article of  claim 15 , wherein the article has been thermoformed and subsequently subjected to injection molding.