| 摘要 |
A corrosion inhibitor especially for antifreeze solutions or hydraulic fluids comprises borax and a primary and/or tertiary phosphate. An alkali salt of mercaptobenzothiazole may be added to the mixture together with a substance (such as a salt of ethylene diamino tetra-acetic acid, of trinitrilo-acetic acid or of polyphosphoric acids) to prevent precipitation of calcium phosphate and an anti-foaming agent such as triethanolamine phosphate The addition of mercaptobenzimidazole is also mentioned. The corrosion inhibitor composition may be added (a) to such anti-freeze agents as monohydric alcohols (e.g. methanol), polyhydric alcohols (e.g. glycols) and dimethyl sulphoxide, (b) to aqueous hydraulic fluids or (c) to water used for cooling vehicle engines during summer. Phosphates mentioned are Na3PO4, KH2PO4, tertiary triethanolamine phosphate, mono- or di-ethanol ammonium phosphate, cyclohexyl ammonium phosphate and morpholine phosphate. In examples, borax, tertiary triethanolamine phosphate and sodium mercaptobenzothiazole are added to ethylene glycol or to a hydraulic fluid consisting of ethylene glycol, diethylene glycol, dipropylene glycol, polyethylene glycol (M.W. 300) and water. |
