You should be able to remove the keys to clean them. When I worked in a school on their computer systems one of our summer holiday jobs when the kids weren't there was to clean all the computer keyboards. We had 147 desktops in the school so it was a big job, anyway the kids used to drop all sorts of stuff into the keyboards. We used to remove all the keys and wash them in warm soapy water and then pop them all back. Usually worked okay as the electronic gubbins had protective film over them so unless the kids had saturated the keyboard with something that was enough to get them working again. Obviously you have to be careful when removing the keys so that you don't break the plastic retaining clips and it only works for desktop type keyboards. You can do it for laptops but you have to be ultra careful with those.