Patent ID: 8357642

Claim:
A brake fluid consisting essentially of: a tetrazole compound (A) contained in an amount of 0.005 mass % to 0.5 mass % with respect to a total mass of the brake fluid, which is selected from the group consisting of 1H-tetrazole, 5-amino-1H-tetrazole, 5-methyl-1H-tetrazole, 1-methyl-5-ethyl-1H-tetrazole, 1-methyl-5-aminotetrazole, 1-methyl-5-mercapto-1H-tetrazole, 1-phenyl-5-mercapto-1H-tetrazole, 1-(2-dimethylaminoethyl)-5-mercapto-1H-tetrazole, 5-phenyl-1H-tetrazole, 5,5′-bis-1H-tetrazole diammonium salt, 4,5-di(5-tetrazolyl)-[1,2,3]triazole, and 5,5′-azobis-1H-tetrazole; a base oil (B) selected from glycols, polymeric derivatives thereof, mixtures thereof, glycol ethers, borate esters, phosphate esters and mixtures of glycols with glycol ethers and/or borate esters or phosphate esters; a triazole compound (C) contained in an amount of 0.005 mass % to 0.5 mass % with respect to a total mass of the brake fluid; and optionally one or more other additives selected from the group consisting of amines, antioxidants, chelating agents, viscosity index improving agents, extreme pressure agents, defoaming agents, and colorants.