Process for the manufacture of a multilayer structure

An organic electronic device

• which is prepared by a process comprising a process for the manufacture of a homojunction multilayer structure suitable for forming part of the organic electronic device having a cathode and an anode, comprising the steps of
• a. depositing a nth layer Ln of the multilayer structure onto a substrate out of a liquid composition Cn comprising a solvent system Sn comprising at least one solvent and at least one organic compound Mi which comprises ionizable groups G which comprise at least one nitrogen atom capable of being reversibly protonated, mainly or totally in neutral (Gn) or mainly or totally in ionized (Gi) form, wherein the substrate is a previously deposited layer Ln−1 of the multilayer structure or is an element suitable for forming the cathode or the anode of the organic electronic device, and thereafter either
• b1.1 evaporating the solvent system Sn to form the dry nth layer and, if the organic compound Mi comprises the group G mainly or totally in its ionized form Gi, converting partly or completely the groups Gi to the neutral form Gn, and
• b1.2 thereafter depositing a (n+1)th layer Ln+1 of the multilayer structure onto the first layer Ln out of a liquid composition Cn+1 comprising a solvent system Sn+1, and organic compound Mi comprising the ionizable group G mainly or totally in ionized form Gi and thereafter
• b1.3. evaporating the solvent system Sn+1 and converting the groups Gi to form the dry (n+1)th layer mainly or totally to the neutral form Gn or,
• b2.1. evaporating the solvent system Sn to form the dry nth layer Ln comprising groups G mainly or totally in ionized form Gi and thereafter
• b2.2. depositing the (n+1)th layer Ln+1 of the multilayer structure onto the dry nth layer Ln out of a liquid composition C(n+1), comprising a solvent system S(n+1), comprising organic compound Mi comprising ionizable groups G mainly or totally in the neutral form Gn and evaporating the solvent system S(n+1), to form a dry (n+1)th layer mainly or totally to the neutral form Gn and thereafter either
• b3.1 depositing a (n+2)th layer out of a liquid composition C(n+2) comprising a solvent system S(n+2) comprising organic compound Mi comprising groups G mainly or totally in the ionized form Gi followed by converting the groups Gi in the dry nth and the dry (n+2)th layer mainly or totally to the neutral form, or
• b3.2 directly converting the groups Gi in the nth layer mainly or totally to the neutral form Gn
• wherein the solubility of organic compound Mi comprising groups G mainly or totally in ionized form Gi in solvent system Sn+1 and Sn+2, different or same, is at least three times as high as the solubility of organic compounds Mi comprising groups G mainly or totally in neutral form Gn in said solvent system Sn+1 and Sn+2, and
• wherein the solubility of organic compounds Mi comprising groups G mainly or totally in neutral form Gn in solvent system S(n+1), is at least three times as high as the solubility of organic compound Mi comprising groups G mainly or totally in ionized form Gi in said solvent system S(n+1),
• the solubility in all cases determined at 23° C. and atmospheric pressure,
• wherein the total content of ionizable groups G of compound gin neutral form is at least 90% and less than 99.9%, based on the total amount of ionizable groups G present in the multilayer device, and
• wherein organic compound Mi comprises a conjugated or non-conjugated polymer having a number average molecular weight of at least 5000 g/mol, and
• wherein the ionizable groups G, which comprise at least one nitrogen atom capable of being reversibly protonated, of the organic compound Mi are part of the conjugated or non-conjugated polymer main chain.