Transparent polymeric electrodes for electro-optical structures, process for producing the same, and dispersions used in such processes

Abstract

The invention concerns a process for producing transparent multi-layer electrodes from conductive polymers, electrodes produced by this process and their use in electro-optical structures.

1 . A process for producing an electrode, the process comprising:
 (a) providing a substrate;   (b) applying a dispersion to the substrate and allowing the dispersion to solidify to form a first layer, wherein the dispersion comprises at least one polymeric anion and at least one polythiophene having repeating units corresponding to the general formula (I):   
       
         
           
           
               
               
           
         
       
       wherein A in each repeating unit independently represents a substituted or unsubstituted C 1  to C 5  alkylene radical, each R independently represents a linear or branched, substituted or unsubstituted C 1  to C 18  alkyl radical, a substituted or unsubstituted C 5  to C 12  cycloalkyl radical, a substituted or unsubstituted C 6  to C 14  aryl radical, a substituted or unsubstituted C 7  to C 18  aralkyl radical, a substituted or unsubstituted C 1  to C 4  hydroxyalkyl radical or a hydroxyl radical, x in each repeating unit independently represents a whole number from 0 to 8, and wherein 50 wt. % of particles in the dispersion are smaller than 50 nm; and
 (c) applying at least one organic hole-injecting material to the first layer to form a second layer. 
 
     
     
         2 . The process according to  claim 1 , wherein the dispersion further comprises one or more additives selected from the group consisting of ether group-containing compounds, lactone group-containing compounds, amide group-containing compounds, lactam group-containing compounds, sulfones, sulfoxides, sugars, sugar derivatives, sugar alcohols, furan derivatives, dialcohols, polyalcohols and mixtures thereof, wherein the one or more additives is present in an amount of at least 0.1 wt. %, based on the dispersion. 
     
     
         3 . The process according to  claim 1 , wherein A in each repeating unit independently represents a substituted or unsubstituted C 2  to C 3  alkyl radical and x in each repeating unit independently represents 0 or 1. 
     
     
         4 . The process according to  claim 1 , wherein the at least one polythiophene having repeating units corresponding to the general formula (I) comprises poly(3,4-ethylenedioxythiophene). 
     
     
         5 . The process according to  claim 1 , wherein the at least one polymeric anion comprises an anion of a polymeric carboxylic or sulfonic acid. 
     
     
         6 . The process according to  claim 1 , wherein the at least one polymeric anion comprises an anion of polystyrene sulfonic acid. 
     
     
         7 . The process according to  claim 4 , wherein the at least one polymeric anion comprises an anion of polystyrene sulfonic acid. 
     
     
         8 . The process according to  claim 1 , wherein the at least one polythiophene having repeating units corresponding to the general formula (I) and the at least one polymeric anion are present in the first layer in a ratio by weight of 0.5:1 to 20:1. 
     
     
         9 . The process according to  claim 1 , wherein the at least one organic, hole-injecting material comprises a substituted or unsubstituted polythiophene having repeating units corresponding to the general formula (II-a) and/or (II-b): 
       
         
           
           
               
               
           
         
         wherein A in each repeating unit independently represents a substituted or unsubstituted C 1  to C 5  alkylene radical, Y in each repeating unit independently represents O or S, each R independently represents a linear or branched, substituted or unsubstituted C 1  to C 18  alkyl radical, a substituted or unsubstituted C 5  to C 12  cycloalkyl radical, a substituted or unsubstituted C 6  to C 14  aryl radical, a substituted or unsubstituted C 7  to C 18  aralkyl radical, a substituted or unsubstituted C 1  to C 4  hydroxyalkyl radical or a hydroxyl radical, x in each repeating unit independently represents a whole number from 0 to 8. 
       
     
     
         10 . The process according to  claim 9 , wherein the substituted or unsubstituted polythiophene having repeating units corresponding to the general formula (II-a) and/or (II-b) is applied to the first layer as a second dispersion, and wherein the second dispersion further comprises at least one polymeric anion. 
     
     
         11 . The process according to  claim 9 , wherein the substituted or unsubstituted polythiophene having repeating units corresponding to the general formula (II-a) and/or (II-b) comprises poly(3,4-ethylenedioxythiophene). 
     
     
         12 . The process according to  claim 11 , wherein the at least one polythiophene having repeating units corresponding to the general formula (I) comprises poly(3,4-ethylenedioxythiophene). 
     
     
         13 . The process according to  claim 1 , wherein the at least one organic, hole-injecting material comprises a doped or undoped material selected from the group consisting of substituted or unsubstituted phthalocyanines, phenylamines and combinations thereof. 
     
     
         14 . An electrode prepared by the process according to  claim 1 . 
     
     
         15 . An electrode prepared by the process according to  claim 4 . 
     
     
         16 . An electrode prepared by the process according to  claim 7 . 
     
     
         17 . The electrode according to  claim 14 , wherein the first layer has a conductivity of at least 300 Scm −1 . 
     
     
         18 . The electrode according to  claim 14 , wherein the first layer has a surface roughness Ra of less than 2.5 nm. 
     
     
         19 . The electrode according to  claim 14 , wherein the first layer has a dry film thickness of 10 to 500 nm. 
     
     
         20 . (canceled) 
     
     
         21 . (canceled) 
     
     
         22 . An electroluminescent arrangement comprising at least two electrodes, and an electro-optically active layer disposed between the at least two electrodes, wherein one of the at least two electrodes is an electrode according to  claim 14 .