| 摘要 |
<p>A process far protecting marble, stones, tiles and articles formed from such materials from the degrading action caused by atmospheric and polluting agents, by applying onto the surfaces thereof a protective agent which is a particularly defined perfluoropolyether, the perfluoropolyether being applied as such or diluted with a solvent or a mixture of solvents having a boiling temperature below 80 DEG C, preferably a chlorofluorohydrocarbon.</p> |
