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).
The benefits of the 'Impervo' tyre product, focusing on preventing heat bursts, valve care, and durability.
| Identifier | ExFiles\Box 77\4\ scan0130 | |
| Date | 10th August 1922 guessed | |
| -3- HEAT BURSTS ELIMINATED. The most important general point regarding "IMPERVO" after puncture-sealing and the maintaining of inflation, is that it keeps the tyres 30% cooler. It has an immediate reducing action on the heat caused by running, and what is still more important, it is designed to absorb and disintegrate the sulphur and chlorine gasses which are thrown off by rubber when it reaches a heat of 97 deg.Fahr. These gasses, which come from the sulphur and chlorine with which rubber is treated in the process of manufacture, cause sudden over-expansion from heat and bring about a full 60% of the bursts which occur on the road. "Impervo" absorbs and renders them harmless as soon as they begin to generate, and there is no possibility of the sudden transition in temperature from 97.deg.Fahr. to bursting point. It will be seen from the above that "Impervo" while it does not eliminate the trouble of bursts, reduces this danger by 80%; a full 60% being attributable to over-expansion by heat and 20% to weaknesses arising from improper inflation. We are of the opinion that this estimated percentage is on the moderate side. VALVES. It cannot be sufficiently insisted upon in demonstrating to prospective users of "Impervo" that particular care should be paid to the re-assembling of the valve parts. This is a commonplace to the motor-mechanic, but in a few cases investigated by the Head Office, it has been found that a driver has re-assembled his valve carelessly or that the valve itself was defective before the wheel was treated with "Impervo". It will be found that far from having an adverse effect on the valve, "Impervo" seems to prevent it from corroding through wet. Should any "Impervo" find its way into the valve itself, which occurs only if the valve is opened with its base actually touching the liquid, it is immediately cleared by the use of the pump. DURABILITY. "Impervo" does not solidify, but has an indefinite liquid life, and it is in no way affected by extremes of temperature, whether of heat or of cold. Care should be taken to use "Impervo" as soon as the tin is opened, for more than temporary exposure to the open air has a deteriorating effect on it, but the half of an opened tin can be kept against future use provided it is placed in an air-tight receptacle. In use "Impervo" lasts the life of an inner tube, as treated inners can be transferred from one cover to another. ------------------- | ||