{HEAD ~ The emissive substance} included in {TAIL ~ the device} is at least one of the following types of compounds: a compound having a plurality of 1,7 phenanthroline skeletal structures; a benzoquinoline derivative; a spiro compound; and a tetraphenylmethane derivative 
included in
{ HEAD ~ The emissive substance } included in { TAIL ~ the device } is at least one of the following types of compounds : a compound having a plurality of 1,7 phenanthroline skeletal structures ; a benzoquinoline derivative ; a spiro compound ; and a tetraphenylmethane derivative
HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH