Printed Stretch Sensor

Abstract

Disclosed is a patterned article comprising: (1) a deformable nonconductive substrate; (2) an imagewise pattern thereon of a conductive stretchable ink; and (3) an external circuit connecting the imagewise pattern, the external circuit being capable of measuring the electrical resistance across regions of the deformable nonconductive substrate and determining the degree of deformation thereof.

What is claimed is: 
     
         1 . A patterned article comprising:
 (1) a deformable nonconductive substrate;   (2) an imagewise pattern thereon of a conductive stretchable ink; and   (3) an external circuit connecting the imagewise pattern, said external circuit being capable of measuring the electrical resistance across regions of the deformable nonconductive substrate and determining the degree of deformation thereof.   
     
     
         2 . An article according to  claim 1  wherein the deformable nonconductive substrate has a resistivity of at least about 1.8×10 5  Ωm. 
     
     
         3 . An article according to  claim 1  wherein the deformable nonconductive substrate has an elasticity in the direction of elongation of at least about 0.0008 MPa. 
     
     
         4 . An article according to  claim 1  wherein the conductive stretchable ink has a conductivity of from about 0.01 μS to about 100 MS. 
     
     
         5 . An article according to  claim 1  wherein the conductive stretchable ink comprises a fluoroelastomer. 
     
     
         6 . An article according to  claim 5  wherein the fluoroelastomer is (a) a copolymer of vinylidene fluoride and hexafluoropropylene; (b) a terpolymer of vinylidene fluoride, hexafluoropropylene, and tetrafluoroethylene; (c) a copolymer of vinylidene fluoride and (per)fluoromethoxyalkylvinylether (d) a terpolymer of vinylidene fluoride, hexafluoropropylene, and polyperfluoromethylvinylether; (e) a terpolymer of vinylidene fluoride, tetrafluoroethylene, and a fluorinated vinyl ether; (f) a terpolymer of vinylidene fluoride, tetrafluoroethylene, and propylene; (g) a tetrapolymer of vinylidene fluoride, hexafluoropropylene, tetrafluoroethylene, and polyperfluoromethylvinylether; (h) a terpolymer of tetrafluoroethylene, propylene, and vinylidene fluoride; (i) a pentapolymer of tetrafluoroethylene, hexafluoroethylene, vinylidene fluoride, ethylene, and polyperfluoromethylvinylether; or (j) a mixture thereof. 
     
     
         7 . An article according to  claim 5  wherein the ink further comprises a surfactant. 
     
     
         8 . An article according to  claim 1  wherein the conductive stretchable ink comprises a conductive pigment selected from carbon black, polypyrrole, polyacetylene, polyaniline, polyphenylene vinylene, polythiophene, polyphenylene sulfide, graphene, silver nanoparticles, copper nanoparticles, or mixtures thereof. 
     
     
         9 . An article according to  claim 1  wherein the conductive stretchable ink is substantially free of silver nanoparticles and copper nanoparticles. 
     
     
         10 . An article according to  claim 1  wherein the conductive stretchable ink is substantially free of silver nanoparticles. 
     
     
         11 . An article according to  claim 1  wherein the imagewise pattern comprises:
 (a) a first set of at least two non-crossing lines of a conductive stretchable ink on a first surface of the deformable nonconductive substrate; and 
 (b) a second set of at least two non-crossing lines of a conductive stretchable ink on a second surface of the deformable nonconductive substrate; 
 wherein at least some of the first set of lines on the first surface cross at least some of the second set of lines on the second surface; and 
 wherein the external circuit connecting the imagewise pattern enables determination of the location of deformation on a surface of the deformable nonconductive substrate. 
 
     
     
         12 . An article according to  claim 11  wherein the conductive stretchable ink comprises a fluoroelastomer. 
     
     
         13 . An article according to  claim 11  wherein the conductive stretchable ink comprises a conductive pigment selected from carbon black, polypyrrole, polyacetylene, polyaniline, polyphenylene vinylene, polythiophene, polyphenylene sulfide, graphene, silver nanoparticles, copper nanoparticles, or mixtures thereof. 
     
     
         14 . An article according to  claim 1  wherein the imagewise pattern comprises at least one line of the conductive stretchable ink on at least one surface of the deformable nonconductive substrate, and wherein the external circuit connecting the imagewise pattern enables determination of the mass of an object situated on the deformable nonconductive substrate. 
     
     
         15 . An article according to  claim 14  wherein the conductive stretchable ink comprises a fluoroelastomer. 
     
     
         16 . An article according to  claim 14  wherein the conductive stretchable ink comprises a conductive pigment selected from carbon black, polypyrrole, polyacetylene, polyaniline, polyphenylene vinylene, polythiophene, polyphenylene sulfide, graphene, silver nanoparticles, copper nanoparticles, or mixtures thereof. 
     
     
         17 . A patterned article comprising:
 (1) a deformable nonconductive substrate having a resistivity of at least about 1.8×10 5  Ωm and an elasticity in the direction of elongation of at least about 0.0008 MPa;   (2) an imagewise pattern thereon of a conductive stretchable ink having a conductivity of from about 0.01 μS to about 100 MS and comprising a fluoroelastomer; and   (3) an external circuit connecting the imagewise pattern, said external circuit being capable of measuring the electrical resistance across regions of the deformable nonconductive substrate and determining the degree of deformation thereof.   
     
     
         18 . A process which comprises:
 (a) applying to a deformable nonconductive substrate in an imagewise pattern a conductive stretchable ink;   (b) connecting the imagewise pattern with an external circuit; and   (c) measuring the electrical resistance across regions of the deformable nonconductive substrate and determining the degree of deformation thereof.   
     
     
         19 . A process according to  claim 18  wherein the imagewise pattern comprises:
 (a) a first set of at least two non-crossing lines of a conductive stretchable ink on a first surface of the deformable nonconductive substrate; and 
 (b) a second set of at least two non-crossing lines of a conductive stretchable ink on a second surface of the deformable nonconductive substrate; 
 wherein at least some of the first set of lines on the first surface cross at least some of the second set of lines on the second surface; and 
 wherein measuring the electrical resistance across regions of the deformable nonconductive substrate enables determination of the location of deformation on a surface of the deformable nonconductive substrate. 
 
     
     
         20 . A process according to  claim 18  wherein the imagewise pattern comprises at least one line of the conductive stretchable ink on at least one surface of the deformable nonconductive substrate, and wherein measuring the electrical resistance across regions of the deformable nonconductive substrate enables determination of the mass of an object situated on the deformable nonconductive substrate.