AA 642 then UA 867 at O'Hare
Dallas-Fort Worth → Chicago → Tokyo Narita
Timetable, Chicago time
13:10AA 642 from Dallas-Fort Worth at the gate
10:40UA 867 to Tokyo Narita leaves the gate
21 h 30 apart on the timetable, overnight
UA 867 leaves 21 h 30 after AA 642 arrives on the timetable: more than half a day, so not a connection we count.