Honestly I would tell them that you're quitting to start a business, but this may depend on your relationship with the manager. You may be able to work somethi

Honestly I would tell them that you're quitting to start a business, but this may depend on your relationship with the manager. You may be able to work something out where you're working part-time, taking a leave of absence or potentially become an early customer. Caveats: 1) Your business is not competing with theirs 2) Does not use any of their IP, 3) You did not use their equipment to make the prototype, 4)You did not sign any legal documents assigning inventions to the company while not on company time