Self-adhesive electrode patch
Disclosed is a layered body comprising a polymer comprising repeating units having the general structure —CH 2 —CHR 1 —COOR 2 — as defined herein, to a process for producing such a layered body, to a layered body produced by that process and to the use of a layered body for electrophysical measurements.
1. A dispersion comprising
i) particles A) of polymer comprising repeating units having the general structure —CH 2 —CR 1 —COOR 2 —
wherein
R 1 represent H or an alkyl group, and
R 2 represents an optionally substituted C 1 -C 10 -alkyl group,
wherein particles A) have a mass average particle diameter (d 50 ) of at least 800 nm;
ii) particles B) of a conductive polymer,
wherein the particles B) have a mass average particle diameter of less than 150 nm;
iii) at least one dispersant;
wherein the weight ratio of the polymer in particles A) to the conductive polymer in particles B) is at least 15:1.
2. The dispersion according to claim 1 , wherein the polymer of particles A) has a glass transition temperature of less than 35° C.
3. The dispersion according to claim 1 , wherein R 1 is H and R 2 is selected from the group consisting of —CH 3 , —CH 2 CH 3 , —C 4 H 9 , —CH 2 CH(C 2 H 5 )(C 4 H 9 ) and —C 8 H 17 .
4. The dispersion according to claim 1 , wherein at least 25% of the repeating units in the polymer of particles A) are monomers in which R 1 is H and R 2 is selected from the group consisting of —CH 3 , —CH 2 CH 3 , —C 4 H 9 , —CH 2 CH(C 2 H 5 )(C 4 H 9 ) and —C 8 H 17 , based on the total number of repeating units in the polymer of particles A).
5. The dispersion according to claim 1 , wherein the polymer of particles A) is a copolymer of acrylic acid or a salt of acrylic acid or both and an acrylic acid ester selected from the group consisting of methyl acrylate, ethyl acrylate, n-butyl acrylate, 2-ethylhexylacrylate and n-octyl acrylate.
6. The dispersion according to claim 1 , wherein the conductive polymer of particles B) comprises a PEDOT/PSS-complex.
7. The dispersion according to claim 1 , wherein the dispersion further comprises, as component iv), a polar high boiling compound having a boiling point (at 1013 mbar) of at least 120° C.
8. A process for producing a layered body, the process comprising
α1) providing a dispersion as defined in claim 2 ;
α2) applying the dispersion onto at least a part of at least one surface of a substrate;
α3) at least partial removal of the dispersant iii) for the formation of a conductive adhesive layer that is superimposed on at least a part of at least one surface of the substrate, wherein the at least partial removal of the dispersant is accomplished by heating the dispersion that has been applied onto the substrate to a temperature above the glass transition temperature of the polymer of particles A).
9. The dispersion according to claim 1 , wherein the dispersant is water.
10. The dispersion according to claim 1 , wherein particles B) of a conductive polymer are particles B) of a complex of a cationic polythiophene and a polymeric anion.
11. The dispersion according to claim 10 , wherein the weight ratio of the polymer in particles A) to the total weight of the cationic polythiophene and the polymeric anion in the complex of particles B) is at least 15:1.
12. The dispersion according to claim 7 , wherein the dispersion further comprises, as component iv), ethylene glycol.