disinfectant cleaners , such as might be used to clean a toilet bowl , are : [ 0044 ] weight percent description chemical name to 100 carrier water 1 . 0 amine oxide alkyl dimethyl surfactant amine oxide . 55 quaternary btc 2125 m disinfectant . 75 nonionic surfactant glucopon 425 n . 65 acid glycolic acid 0 . 1 poly d - glucosamine chitosan 0 . 1 furanone furanone 30 , 1 % in ethyl alcohol . 57 butyl cellosolve ethylene glycol butyl ether . 43 hexyl cellosolve ethylene glycol hexyl ether . 268 base sodium hydroxide [ 0045 ] weight percent description chemical name to 100 carrier water 0 . 75 nonionic surfactant glucopon 425 n 0 . 10 furanone furanone 30 , 1 % in ethyl alcohol 2 . 50 acid lactic or glycolic acid 0 . 25 poly d - glucosamine chitosan [ 0046 ] weight percent description chemical name 94 . 828 carrier water 1 nonionic surfactant glucopon 425 n . 572 acid glycolic acid 0 . 5 poly d - glucosamine chitosan 0 . 1 furanone furanone 30 , 1 % in ethyl alcohol 3 butyl propasol propylene glycol n - butyl ether [ 0047 ] weight percent description chemical name 97 . 828 carrier water 1 nonionic surfactant glucopon 425 n . 572 acid glycolic acid 0 . 5 poly d - glucosamine chitosan 0 . 1 furanone furanone 30 , 1 % in ethyl alcohol [ 0048 ] weight percent description chemical name 95 . 828 carrier water . 572 acid glycolic acid 0 . 5 poly d - glucosamine chitosan 0 . 1 furanone furanone 30 , 1 % in ethyl alcohol 3 butyl propasol propylene glycol n - butyl ether [ 0049 ] weight percent description chemical name 98 . 828 carrier water . 572 acid glycolic acid 0 . 5 poly d - glucosamine chitosan 0 . 1 furanone furanone 30 , 1 % in ethyl alcohol furanone 30 is the “ furanone 30 ” referred to in fig5 . this can be synthesized by known techniques . the samples we used for our testing were supplied by the university of new south wales centre for marine biofouling and bio - innovation , sydney , australia . the above cleaners can be formulated by adding the components to water and then mixing at room temperature . where an anionic surfactant is to be added , it is preferable to first add the nonionic surfactant and chitosan ( as anionic surfactants alone may cause instability for the chitosan ). we tested the formulations of examples 3 - 6 , as well as a control containing 99 . 428 % water and 0 . 572 glycolic acid , as well as a control containing just water . 4 ″× 4 ″ ceramic tiles ( glazed ) were sprayed with the formulas ( 3 - 5 times ) at a distance of 6 inches . each formula was allowed to remain on its respective tile for 10 minutes . each tile was then wiped two times back and forth with a sterile paper towel . after 24 hours , the tiles were dry wiped two times , back and forth with a sterile paper towel . the towels were then inoculated with 0 . 5 ml of 10 6 of staph aureus . after ten minutes a rodak plate ( made with d / e neutralizing agar ) was pressed and rocked onto the tile . the rodak plates were then placed into an incubator set at about 32 ° c . after two days , the plates were observed for organism growth . the deionized water plate was completely covered with organisms . the water / acid control plate contained many organisms , but less organisms than the deionized water control . the other formula led to zero organisms in most circumstances , or at worst only one organism was visible on the tile . this confirms that formulas containing chitosan and furanone provide surprising residual antimicrobial benefit , even after the tile had been wiped back and forth after the spraying . thus , the present invention provides effective cleaners that not only clean hard surfaces , but also leave desirable residual properties on those surfaces after the cleaning . while the preferred embodiment incorporates chitosan , other poly d - glucosamines ( e . g . substituted chitosans ) can also be used . also , while brominated furanones are highly preferred for the present purposes , a wide variety of furanones can be used for these purposes . thus , while specific embodiments have been described , various modifications falling within the breadth and scope of the invention . the following claims should be looked to in order to understand the full scope of the invention .