The most comfortable chair I've ever plunked my rump into was an Eames lounge chair knock-off that my folks had back in the 70s and 80s. A genuine Eames chair would set you back several thousands, but a good "Eames style" chair can be had for much less. I haven't looked in years, but probably a couple of hundred. Quality will vary greatly among the knock-offs, so shop carefully, but the one my folks had lasted many years.
If you Google "Eames lounge chair" you'll see plenty of examples.
Also, I found a Wikipedia entry:
https://en.wikipedia.org/wiki/Eames_Lounge_Chair