| abstract |
Organic light emitting devices are disclosed which are comprised of an organic charge carrier layer formed from a charge carrier material that is capable of forming a stable glass due to the presence of a compound having an asymmetric molecular structure in the charge carrier material. For example, the OLED may contain hole transporting layers comprised of compounds having an asymmetric molecular structure in which hole transporting substituents are asymmetrically located around a core atom or core chemical group. The core atom may be a nitrogen atom or the core chemical group may be comprised of a single phenylene group or a biphenylene group which is substituted with at least two hole transporting amine groups, wherein at least one of the amine groups is different from at least one other amine group. For example, the compound may have the asymmetric molecular structure as shown by formula (I), wherein R1, R2, R3, R4, R5 and R6 are, independently of one another, hole transporting amine groups, or hydrogen, with the proviso that at least two amine groups are present and at least one of the amine groups is different from at least one other amine group. Typically, R1 and R4 are hole transporting amine groups wherein R1 is different from R4. |