HYDRAULIC FLUIDS CONTAINING ORTHOSILICATE ESTERS

摘要

1464712 Hydraulic fluid CASTROL Ltd 9 Jan 1974 [10 Jan 1973] 1409/73 Heading C5F [Also in Division C3] A hydraulic fluid comprises an orthosilicate ester of the formula wherein R1 denotes a propylene glycol monoalkyl ether residue in which the terminal alkyl group contains from 1 to 8 carbon atoms, or a tertiary alkyl group, each of R2, R3 and R4 independently denote an ethylene or propylene glycol monoalkyl ether residue in which the terminal alkyl group contains from 1 to 8 carbon atoms, or a tertiary alkyl group, provided that (1) when R1 denotes a propylene glycol monoalkyl ether residue each of R2, R3 and R4 also denote propylene glycol monoalkyl ether residues, (2) the total number of carbon atoms in R1, R2, R3 and R4 is at least 15, and (3) at least one of R1, R2, R3 and R4 denotes a glycol monoalkyl ether residue, alone or in admixture with conventional hydraulic fluid base stocks and/or conventional additives such as lubricity additives, corrosion inhibitors and antioxidants.