It really depends on how you define laptop. There was this sort of thing in the 80s, (https://en.wikipedia.org/wiki/Toshiba_T1100), of course. And there were a couple of laptop-shaped laptops from 1988 on, but they were either spectacularly compromised (the NEC Ultralite had a max of 2MB of storage, for instance) or spectacularly expensive or both. In terms of laptops that were shaped like laptops as we know them, and that were actually usable outside of very specialized applications, the Powerbook 100 and Thinkpad 700T could be reasonably claimed to be about the first.