Resistance to Antiseptics
For some classes of antiseptics the effect is more simple chemistry or even physics than biochemical toxicity. Ethanol will just denature proteins and dissolve the membrane, and the used concentration of ethanol is so high that no amount of efflux pumps is going to save the bacterium. Some other compounds work in a similar brute force way: QACs will break the membranes, hydrogen peroxide will just oxidize everything. For iodine (like in PVP-1) the mechanism is not really known, but probably it also just reacts with all kinds of things in/on the bacterial cell and kill them. 

Antiseptic resistance could happen for some other antiseptics (or low concentrations of the compounds mentioned above). For some antibiotics, resistance is caused by the expression of efflux pumps that just pump out enough antibiotics so the cell survives. Bacteria could do the same for these antiseptics. The reason why it's not that much of an issue is that the application is rather different. Antibiotics are for inside use, antiseptics for topical use, you cannot just flood your whole body with 70% ethanol to kill all bacteria, but for a wound / something dirty this is just fine. This makes it much easier to avoid creating resistance.