You need an internegative, either a film or paper one. I've had interesting results with PolaPan slide film (you'll need a special processor for that type) and making a high-contrast paper internegative. It gives a kind of softy look, so if you want sharply focused you may want to try something else. There are not very many b+w slide films available, and none that you can process using regular negative chemistry. So maybe you are talking about Cibachromes? For those you would need a dichroic head enlarger, processing drum, whole different set of chemicals, process in complete darkness, etc. Is there a certain look you are going for? Maybe there is a way to do it using negative film.