Will depend on how much time you are spending on the business, not the amount of money you are making (or not making). To be eligible for a Jobseekers payment you must be unemployed on at least 3 days out of 6 (Sundays don't count), looking for and available for full-time work. Of course, you also need to have sufficient PRSI contributions paid at Class A (you pay Class S if you are self-employed) so you may not have the contributions unless you were also working as an employee as well.
If you don't have the PRSI contributions for Jobseekers BEnefit, you may still be eligible for Jobseekers Allowance. You still have to be unemployed on at least 3 days out of 6, but also any income from your self employment is averaged over a representative period and deducted from any payment you may receive. If you are not making any money, and are not working more than 3 days in the business then you should be able to get a full Jobseekers Allowance payment provided you can demonstrate that you are genuinely seeking full-time work.