Patent ID: 7377983

Claim:
A method for preventing formation of deposits on a ceramic surface comprising: (1) pretreating the surface by applying an aqueous solution containing from about 200 ppm to about 1000 ppm by weight of an amphoteric fluorosurfactant having the formula R f —CH 2 CH 2 —SO 2 NH(CH 2 ) 3 —N + (CH 3 ) 2 CH 2 COO − wherein R f is CF 3 CF 2 (CF 2 CF 2 ) x and x is 2 to 7, and (2) periodically applying an aqueous maintenance solution comprising from about 1 ppm to about 200 ppm of said amphoteric fluorosurfactant or a mixture thereof, from about 5 ppm to about 100 ppm of a sequestering acid, and from about 2.5 ppm to about 200 ppm of a quaternary ammonium biocide compound, wherein all concentrations are by weight of aqueous solution.