From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Patent for Prestone anti-freeze and the viability of manufacturing a competing product.
| Identifier | ExFiles\Box 151\3\ scan0172 | |
| Date | 29th April 1932 | |
| W/N. A.{Mr Adams} From Hs{Lord Ernest Hives - Chair}/Lid.{A. J. Lidsey} X(4)35 Hs{Lord Ernest Hives - Chair}/Lid.{A. J. Lidsey}9/MA.29.4.32. ANTI FREEZING COMPOUNDS. A.19/H.28.4.32. We have obtained the patent specification under which Prestone is manufactured, the patent covers the use of ethylene glycol, trimethylene glycol and other glycols when mixed with water over a range of 60 to 65 parts of water and 35 to 40 parts of glycols for use as a heating and refrigerating liquid. Broadly it appears to prevent the use of glycols as a proprietory anti freezing mixture. It is therefore scarcely worth while taking the matter up further with any manufacturers; we know that ethylene glycol can be obtained from Imperial Chemical Industries and is generally used by the Air Force as an anti freezing mixture in aero engines; if it were possible to manufacture and market it as an anti freezing compound without infringing patents someone would by now have done so. Hs{Lord Ernest Hives - Chair}/A.J.Lidsey. | ||