I'd pick a different disinfectant than bleach for cleaning a non-industrial knife handle. Bleach is intended to remove colors from materials using an oxidation process. It contains chlorine which not only eats colors it also attacks most organic-based materials like rubber, synthetic rubber, and many plastics. Things that tolerate bleach are plastics like polyethelene (used in bleach bottles). I happily bleach my white plastic handled industrial boning knife, but not my regular hunting knives.
I get gallon jugs of concentrated Lysol Lemon Scent cleaner/disinfectant at Sam's Club. I mix diluted solution and fill a spray bottle. This is a lot less obnoxious to have around than bleach. Have you ever noticed that it seems to take forever to completely rinse bleach off of something?
I just got some European military surplus field gear this week. It all came with some degree of mildew odor. The Lysol cleaner works on a variety of materials without discoloring them.
There are many other brands of disinfectants out there. I'd leave bleach for cases where I wanted a color removal effect along with disinfecting.