I'm on last year of my Ph.D. However, I got an offer from investors for my project and investor required to full-time work in a new company. Would it be an advantage or a disadvantage to have worked for a couple of years, when continuing Ph.D. again later?
Ultimately this is a personal decision, but I'll offer a few things to consider. Depending on your field and your specific research, taking time out might be a large set-back, or not. The world of research won't stand still while you are away and you might get pre-empted by a delay that might wind up to be longer than you first plan for.
Your advisor should also be able to give good advice on this as s/he likely knows the field and what are the prospects of returning smoothly. Your advisor might, also, be willing to wait for you, or not, so it is good to check.
Finally, what do you really want to do with your life? If it is to be an academic, primarily, think harder about finishing. If it is to be an entrepreneur, then the degree may not mean as much to you as taking advantage of the new opportunity. The industry experience might have some, but not likely a lot, of advantage in seeking an academic position later. Not a "slam dunk", anyway.
Finally, make sure that you understand what the conditions would be if you join up with these investors. Are you a full partner, or are you being used? Either is possible in the somewhat messy real world.
Try to have your cake and eat it too. See if the completion of the Ph.D. can be accelerated (many people spend way too much time on their thesis...just jam that thing out). Perhaps you can start part time with the startup or defer it (or even get some subtle influence to pull to completion because there is a job waiting).
I am not an academia lover (the converse), but I would be extremely hesitant about busting out of your Ph.D. a year from completion. That is a lot to walk away from. Wouldn't do it for a cushy industry job and for a startup (higher risk), it makes even less sense. Get that Ph.D. done. How good the Ph.D. is, matters much less than if it is done (very digital, not analog). There will be other startups. But it would be nice to have that degree done.