Another useful alcohol in the holographic darkroom, its principal use is for the drying of gelatin layers, most typically for the dichromated gelatin process, but can be applied to silver halide work, either with the typical processing that keeps the silver in the emulsion, or with its removal, as in a Silver Halide Sensitized Gelatin process. It is also a good disinfectant, and can relax muscles.
Here is what the Photo-Lab Index from Morgan & Morgan has to say about it:
This chemical can be bought in a drug store. The less expensive bottles contain 70% isopropyl, 30% water (by weight or volume?) and also in 91% solutions. The 100% (or a close enough 99%) solution can be found in the solvent section of building supply stores.