Since it is impossible to get certain cleaning solutions (in Canada, at least) like "Eclipse" (methanol) and pure isopropyl alcohol (from drug stores) is adulterated with some kind of greasy oils that leave smear marks behind, I would appreciate some help as to what chemical solutions might be available to do the job? What is required is merely that there be no residue left when cleaning the CCD. For instance, I have found 94% pure alcohol (from the government owned SAQ alcohol controlled stores in Quebec). My question is: just what might the remaining 6% contain? and How can I find out what that might be? My "long ago an far away" studies in chemistry suggest that that would be H2O; but I am skeptical of the reliability of the SAQ. Thanks for any help.