Patent GB-734644-A (GB)
Title: Compositions suitable for use as hydraulic fluids
Inventor: DAVIES PETER LAVEROCK
IPC: C10M169/04
Filed: 1953-07-17
Abstract: Compositions suitable for use as hydraulic fluids comprise 15 to 80 per cent of a normally liquid trialkyl phosphate containing at least 12 carbon atoms in the molecule, 1 to 15 per cent of a polymer of an ester of acrylic or alkyl acrylic acid, and 10 to 70 per cent of a normally liquid chlorinated, fluorinated, or chlorofluorinated hydrocarbon having a boiling point above 75 DEG  C. Trialkyl phosphates specified are tri-n-butyl, tri-n-amyl, tri-2-ethylbutyl, tri-n-hexyl, tri-2-ethylhexyl, tri-n-octyl, and tri-(3,5,5-trimethylhexyl) phosphates; in order to reduce inflammability the compositions may also contain up to 50 per cent of phosphates containing aryl groups such as tricresyl, trixylenyl, diphenyl cresyl, phenyl dicresyl, diphenyl xylenyl, diphenyl ethylphenyl, diphenyl o-chlorophenyl, octyl diphenyl, dihexyl cresyl, octyl phenyl cresyl, and butyl octyl cresyl phosphates, and also phosphates containing tolyl, cumenyl, and pseudo-cumenyl groups. Polymers of esters of acrylic and alkyl acrylic acids specified are those made from the methyl, ethyl, n-propyl, isopropyl, isobutyl, lauryl, phenyl, or benzyl esters of acrylic, methacrylic, ethylacrylic, and propylacrylic acids, alone or in admixture with one another.  The polymeric esters may be used in the form of concentrated dispersions in mineral oil. Halogenated hydrocarbons specified are carbon tetrachloride, ethylene dichloride, trichloroethylene, tetrachloroethylene, hexachlorobutadiene, o-dichlorobenzene, m-dichlorobenzene, chlorinated diphenyls, 1,2,4-trichlorobenzene, chlorin, ated cumene, tetrafluorotetrachloropropane-pentachlorotrifluoropropane, perfluorochloropentanes, perfluorochlorohexanes, perfluoroheptane, perfluoro-2,2,4-trimethyl pentane, perfluorobutandiene dimer and trimer, fluorinated kerosine and light lubricating oil distillates, liquid polymers of difluorovinyl chlorides and chlortrifluoroethylene, perfluoromethylcyclohexane, the perfluoro ortho-, meta-, and para-dimethylcyclohexanes, perfluoro-1,3,5-trimethylcyclohexane, perfluoronaphthalene and its methyl and dimethyl homologues, perfluorobenzene, perfluorotoluene, chloro-1,3-bis - (trifluoromethyl) benzene, dichloro - (trifluoromethyl) benzene, dichloro-bis-(trifluoro-methyl) benzene, chloro-1-(trifluoromethyl)-4-(chlorotetrafluoroethyl) benzene, trichlorobenzotrifluoride, and tetrachlorobenzotrifluoride.  Also present in the compositions as corrosion inhibitors and anti-oxidants may be epoxy compounds such as glycidyl phenyl, glycidyl benzyl, glycidyl cyclohexyl, glycidyl o-cresyl, glycidyl methyl, and glycidyl isopropyl ethers, isobutylene oxide, butadiene monoxide, styrene oxide, cyclohexylene oxide, cyclopentene oxide, decene oxide, 2,3-epoxybutane, 1,2-epoxybutane, and epichlorhydrin; these epoxy compounds may be used alone or in combination with sulphur containing organic compounds for example butyl disulphide, benzyl disulphide, wax disulphide, di-n-propyl disulphide, di-isoamyl disulphide, diphenyl disulphide, and alkyl mercaptans.  Alternatively there may be used as inhibitors organic salts of Group II metals, such as the zinc and cadmium salts of alkylated salicyclic acids, alkyl malonic acids, condensation products of sulphanols with unsaturated carboxylic acids, hydrocarbon sulphonic acids, and aminophenols.