Planarizing agents and devices
View Patent ↗Use of certain materials in hole injection layer and/or hole transport layer can improve operational lifetimes in organic devices. Polymers having fused aromatic side groups such as polyvinylnaphthol polymers can be used in conjunction with conjugated polymers. Inks can be formulated and cast as films in organic electronic devices including OLEDs, SMOLEDs, and PLEDs. One embodiment provides a composition comprising: at least one conjugated polymer, and at least one second polymer different from the conjugated polymer comprising at least one optionally substituted fused aromatic hydrocarbon side group. The substituent can be hydroxyl. Aqueous-based inks can be formulated.
1. A composition comprising:
at least one conjugated polymer, and
at least one second polymer different from the conjugated polymer comprising at least one substituted fused aromatic hydrocarbon side group, wherein the second polymer has a number average molecular weight between 5,000 g/mol and 100,000 g/mol, wherein the fused aromatic hydrocarbon side group is substituted with an amino or thiol group,
wherein the composition is formulated for use as a hole injection or hole transport layer in an organic device.
2. The composition of claim 1 wherein the fused aromatic hydrocarbon side group is substituted with the amino group.
3. The composition of claim 1 wherein the fused aromatic hydrocarbon side group is substituted with a thiol group.
4. The composition of claim 1 , wherein the fused aromatic hydrocarbon side group is a naphthalene group.
5. The composition of claim 1 , wherein the second polymer comprises a carbon backbone and the substituted fused aromatic hydrocarbon side group comprises two fused benzene rings.
6. The composition of claim 1 wherein the second polymer provides a decreased singlet and/or triplet excited state energy.
7. The composition of claim 1 wherein the second polymer is an excited state stabilizer.
8. The composition of claim 1 wherein the second polymer has a number average molecular weight between 5,100 g/mol and 34,000 g/mol.
9. The composition of claim 1 , wherein the first and second polymers are at least partially soluble or dispersible in water.
10. The composition of claim 1 wherein the conjugated polymer is a heterocyclic polymer.
11. The composition of claim 1 wherein the conjugated polymer comprises a polythiophene backbone.
12. The composition according to claim 1 , wherein the composition further comprises
a solvent carrier for the conjugated polymer and the second polymer.
13. A device comprising a layer comprising the composition of claim 1 .
14. The device of claim 13 , wherein the layer is a hole injection layer or a hole transport layer.
15. The device of claim 13 , wherein the device is an OLED device.
16. A method of making a device comprising:
providing a substrate;
layering a transparent conductor on the substrate;
providing a composition comprising at least one conducting polymer comprising conjugated units, and at least one second polymer comprising fused aromatic hydrocarbon side groups, wherein the second polymer has a number average molecular weight between 5,000 g/mol and 100,000 g/mol, and wherein the fused aromatic hydrocarbon side groups are substituted with an amino or thiol group;
layering the composition on the transparent conductor to form a hole injection layer or hole transport layer;
layering an active layer on the hole injection layer or hole transport layer; and
layering a cathode on the active layer.
17. A method comprising: applying the composition of claim 1 as part of an HIL or HTL layer in an OLED, a photovoltaic device, an ESD, a SMOLED, a PLED, a sensor, a supercapacitor, a cation transducer, a drug release device, an electrochromic device, a transistor, a field effect transistor, an electrode modifier, an electrode modifier for an organic field transistor, an actuator, or a transparent electrode.